diff --git a/modules.yaml b/modules.yaml
index ceff427..75bc913 100644
--- a/modules.yaml
+++ b/modules.yaml
@@ -6,6 +6,7 @@ modules:
         output: jsix.elf
         target: host
         deps:
+            - cpu
             - kutil
         includes:
             - src/kernel
@@ -62,6 +63,8 @@ modules:
         kind: exe
         target: boot
         output: boot.efi
+        deps:
+            - cpu
         source:
             - src/boot/main.cpp
             - src/boot/console.cpp
@@ -110,6 +113,14 @@ modules:
             - src/libraries/kutil/memory.cpp
             - src/libraries/kutil/printf.c
 
+    cpu:
+        kind: lib
+        output: libcpu.a
+        includes:
+            - src/libraries/cpu/include
+        source:
+            - src/libraries/cpu/cpu.cpp
+
 
     libc:
         kind: lib
diff --git a/src/boot/console.cpp b/src/boot/console.cpp
index b679735..02c9181 100644
--- a/src/boot/console.cpp
+++ b/src/boot/console.cpp
@@ -70,8 +70,8 @@ console::console(uefi::boot_services *bs, uefi::protos::simple_text_output *out)
 			type = L"unknown";
 		}
 
-		printf(L"Found framebuffer: %dx%d type %s @0x%x\r\n",
-			m_fb.horizontal, m_fb.vertical, type, m_fb.phys_addr);
+		printf(L"Found framebuffer: %dx%d[%d] type %s @0x%x\r\n",
+			m_fb.horizontal, m_fb.vertical, m_fb.scanline, type, m_fb.phys_addr);
 	} else {
 		printf(L"No framebuffer found.\r\n");
 	}
diff --git a/src/boot/main.cpp b/src/boot/main.cpp
index 3f74ee4..f48e3b8 100644
--- a/src/boot/main.cpp
+++ b/src/boot/main.cpp
@@ -8,6 +8,7 @@
 #include <stdint.h>
 
 #include "console.h"
+#include "cpu/cpu.h"
 #include "error.h"
 #include "fs.h"
 #include "hardware.h"
@@ -94,6 +95,28 @@ add_module(args::header *args, args::mod_type type, buffer &data)
 	m.size = data.size;
 }
 
+/// Check that all required cpu features are supported
+void
+check_cpu_supported()
+{
+	status_line status {L"Checking CPU features"};
+
+	cpu::cpu_id cpu;
+	uint64_t missing = cpu.missing();
+	if (missing) {
+#define CPU_FEATURE_OPT(...)
+#define CPU_FEATURE_REQ(name, ...) \
+		if (!cpu.has_feature(cpu::feature::name)) { \
+			status::fail(L"CPU required feature " L ## #name, uefi::status::unsupported); \
+		}
+#include "cpu/features.inc"
+#undef CPU_FEATURE_REQ
+#undef CPU_FEATURE_OPT
+
+		error::raise(uefi::status::unsupported, L"CPU not supported");
+	}
+}
+
 /// The main procedure for the portion of the loader that runs while
 /// UEFI is still in control of the machine. (ie, while the loader still
 /// has access to boot services.
@@ -160,6 +183,7 @@ efi_main(uefi::handle image, uefi::system_table *st)
 {
 	using namespace boot;
 	console con(st->boot_services, st->con_out);
+	check_cpu_supported();
 
 	args::header *args = uefi_preboot(image, st);
 	memory::efi_mem_map map = uefi_exit(args, image, st->boot_services);
diff --git a/src/boot/memory.cpp b/src/boot/memory.cpp
index e283ed9..92bafa5 100644
--- a/src/boot/memory.cpp
+++ b/src/boot/memory.cpp
@@ -36,6 +36,15 @@ static const wchar_t *memory_type_names[] = {
 	L"persistent memory"
 };
 
+static const wchar_t *kernel_memory_type_names[] = {
+	L"free",
+	L"pending",
+	L"acpi",
+	L"uefi_runtime",
+	L"mmio",
+	L"persistent"
+};
+
 static const wchar_t *
 memory_type_name(uefi::memory_type t)
 {
@@ -45,6 +54,12 @@ memory_type_name(uefi::memory_type t)
 	return L"Bad Type Value";
 }
 
+static const wchar_t *
+kernel_memory_type_name(kernel::args::mem_type t)
+{
+	return kernel_memory_type_names[static_cast<uint32_t>(t)];
+}
+
 void
 update_marked_addresses(uefi::event, void *context)
 {
@@ -144,6 +159,7 @@ build_kernel_mem_map(kernel::args::header *args, uefi::boot_services *bs)
 	bool first = true;
 	for (auto desc : map) {
 		/*
+		// EFI map dump
 		console::print(L"   Range %lx (%lx) %x(%s) [%lu]\r\n",
 			desc->physical_start, desc->attribute, desc->type, memory_type_name(desc->type), desc->number_of_pages);
 		*/
@@ -165,6 +181,7 @@ build_kernel_mem_map(kernel::args::header *args, uefi::boot_services *bs)
 
 			case uefi::memory_type::loader_data:
 				type = mem_type::pending;
+				break;
 
 			case uefi::memory_type::runtime_services_code:
 			case uefi::memory_type::runtime_services_data:
@@ -216,6 +233,15 @@ build_kernel_mem_map(kernel::args::header *args, uefi::boot_services *bs)
 	args->mem_map = kernel_map;
 	args->map_count = i;
 
+	/*
+	// kernel map dump
+	for (unsigned i = 0; i < args->map_count; ++i) {
+		const kernel::args::mem_entry &e = kernel_map[i];
+		console::print(L"   Range %lx (%lx) %x(%s) [%lu]\r\n",
+			e.start, e.attr, e.type, kernel_memory_type_name(e.type), e.pages);
+	}
+	*/
+
 	return map;
 }
 
diff --git a/src/boot/paging.cpp b/src/boot/paging.cpp
index 21f693d..b1423fb 100644
--- a/src/boot/paging.cpp
+++ b/src/boot/paging.cpp
@@ -28,7 +28,7 @@ using ::memory::table_entries;
 /// Page table entry flags for entries pointing at a page
 constexpr uint16_t page_flags = 0x103;
 
-// Flags: 0  0 0 0 1  1 0 0 0  0 0 1 1 = 0x0183
+// Flags: 0  0 0 0 1  1 0 0 0  1 0 1 1 = 0x018b
 //        |   IGN  |  | | | |  | | | +- Present
 //        |        |  | | | |  | | +--- Writeable
 //        |        |  | | | |  | +----- Supervisor only
@@ -209,11 +209,14 @@ allocate_tables(kernel::args::header *args, uefi::boot_services *bs)
 
 	bs->set_mem(addr, tables_needed*page_size, 0);
 
-	args->pml4 = addr;
+	page_table *pml4 = reinterpret_cast<page_table*>(addr);
+
+	args->pml4 = pml4;
 	args->table_count = tables_needed - 1;
 	args->page_tables = offset_ptr<void>(addr, page_size);
 
-	page_table *pml4 = reinterpret_cast<page_table*>(addr);
+	console::print(L"    First page (pml4) at: 0x%lx\r\n", pml4);
+
 	add_kernel_pds(pml4, args->page_tables, args->table_count);
 	add_offset_mappings(pml4, args->page_tables, args->table_count);
 
diff --git a/src/drivers/fb/main.cpp b/src/drivers/fb/main.cpp
index 2f02053..efedc50 100644
--- a/src/drivers/fb/main.cpp
+++ b/src/drivers/fb/main.cpp
@@ -60,6 +60,7 @@ main(int argc, const char **argv)
 	screen::pixel_t fg = scr.color(0xb0, 0xb0, 0xb0);
 	screen::pixel_t bg = scr.color(49, 79, 128);
 	scr.fill(bg);
+	scr.update();
 
 	constexpr int margin = 2;
 	const unsigned xstride = (margin + fnt.width());
@@ -85,11 +86,13 @@ main(int argc, const char **argv)
 			scroll.add_line(e->message, eom);
 			if (++pending > pending_threshold) {
 				scroll.render(scr, fnt);
+				scr.update();
 				pending = 0;
 			}
 		} else {
 			if (pending) {
 				scroll.render(scr, fnt);
+				scr.update();
 				pending = 0;
 			}
 		}
diff --git a/src/drivers/fb/screen.cpp b/src/drivers/fb/screen.cpp
index a01823b..d7862f9 100644
--- a/src/drivers/fb/screen.cpp
+++ b/src/drivers/fb/screen.cpp
@@ -1,3 +1,5 @@
+#include <stdlib.h>
+#include <string.h>
 #include "screen.h"
 
 screen::screen(void *addr, unsigned hres, unsigned vres, pixel_order order) :
@@ -6,6 +8,7 @@ screen::screen(void *addr, unsigned hres, unsigned vres, pixel_order order) :
 	m_resx(hres),
 	m_resy(vres)
 {
+	m_back = reinterpret_cast<pixel_t*>(malloc(hres*vres*sizeof(pixel_t)));
 }
 
 screen::pixel_t
@@ -31,11 +34,17 @@ screen::fill(pixel_t color)
 {
 	const size_t len = m_resx * m_resy;
 	for (size_t i = 0; i < len; ++i)
-		m_fb[i] = color;
+		m_back[i] = color;
 }
 
 void
 screen::draw_pixel(unsigned x, unsigned y, pixel_t color)
 {
-	m_fb[x + y * m_resx] = color;
+	m_back[x + y * m_resx] = color;
+}
+
+void
+screen::update()
+{
+	memcpy(m_fb, m_back, m_resx*m_resy*sizeof(pixel_t));
 }
diff --git a/src/drivers/fb/screen.h b/src/drivers/fb/screen.h
index a9766ec..8d338ce 100644
--- a/src/drivers/fb/screen.h
+++ b/src/drivers/fb/screen.h
@@ -19,8 +19,10 @@ public:
 	void fill(pixel_t color);
 	void draw_pixel(unsigned x, unsigned y, pixel_t color);
 
+	void update();
+
 private:
-	pixel_t *m_fb;
+	pixel_t *m_fb, *m_back;
 	pixel_order m_order;
 	unsigned m_resx, m_resy;
 
diff --git a/src/kernel/cpu.cpp b/src/kernel/cpu.cpp
index 7e6c25b..4b0720e 100644
--- a/src/kernel/cpu.cpp
+++ b/src/kernel/cpu.cpp
@@ -1,116 +1,31 @@
 #include <stdint.h>
+#include "kutil/assert.h"
 #include "kutil/memory.h"
 #include "cpu.h"
+#include "cpu/cpu.h"
 #include "log.h"
 
 cpu_data bsp_cpu_data;
 
-static constexpr uint32_t cpuid_extended = 0x80000000;
-
-
-inline static void
-__cpuid(
-	uint32_t leaf,
-	uint32_t subleaf,
-	uint32_t *eax,
-	uint32_t *ebx = nullptr,
-	uint32_t *ecx = nullptr,
-	uint32_t *edx = nullptr)
-{
-	uint32_t a, b, c, d;
-	__asm__ __volatile__ ( "cpuid"
-			: "=a"(a), "=b"(b), "=c"(c), "=d"(d)
-			: "a"(leaf), "c"(subleaf)
-			);
-	if (eax) *eax = a;
-	if (ebx) *ebx = b;
-	if (ecx) *ecx = c;
-	if (edx) *edx = d;
-}
-
-cpu_id::cpu_id() :
-	m_features(0)
-{
-	__cpuid(0, 0,
-		&m_high_basic,
-		reinterpret_cast<uint32_t *>(&m_vendor_id[0]),
-		reinterpret_cast<uint32_t *>(&m_vendor_id[8]),
-		reinterpret_cast<uint32_t *>(&m_vendor_id[4]));
-
-	__cpuid(cpuid_extended, 0, &m_high_ext);
-
-	if (m_high_ext >= cpuid_extended + 4) {
-		__cpuid(cpuid_extended + 2, 0,
-			reinterpret_cast<uint32_t *>(&m_brand_name[0]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[4]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[8]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[12]));
-		__cpuid(cpuid_extended + 3, 0,
-			reinterpret_cast<uint32_t *>(&m_brand_name[16]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[20]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[24]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[28]));
-		__cpuid(cpuid_extended + 4, 0,
-			reinterpret_cast<uint32_t *>(&m_brand_name[32]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[36]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[40]),
-			reinterpret_cast<uint32_t *>(&m_brand_name[44]));
-	} else {
-		m_brand_name[0] = 0;
-	}
-}
-
-cpu_id::regs
-cpu_id::get(uint32_t leaf, uint32_t sub) const
-{
-	regs ret {0, 0, 0, 0};
-
-	if ((leaf & cpuid_extended) == 0 && leaf > m_high_basic) return ret;
-	if ((leaf & cpuid_extended) != 0 && leaf > m_high_ext) return ret;
-
-	__cpuid(leaf, sub, &ret.eax, &ret.ebx, &ret.ecx, &ret.edx);
-	return ret;
-}
-
 void
-cpu_id::validate()
+cpu_validate()
 {
-	bool fail = false;
-	uint32_t leaf = 0;
-	uint32_t sub = 0;
-	regs r;
+	cpu::cpu_id cpu;
 
-	log::info(logs::boot, "CPU: %s", brand_name());
-	log::debug(logs::boot, "    Vendor is %s", vendor_id());
+	log::info(logs::boot, "CPU: %s", cpu.brand_name());
+	log::debug(logs::boot, "    Vendor is %s", cpu.vendor_id());
 
-	log::debug(logs::boot, "    Higest basic CPUID: 0x%02x", highest_basic());
-	log::debug(logs::boot, "    Higest ext CPUID:   0x%02x", highest_ext() & ~cpuid_extended);
+	log::debug(logs::boot, "    Higest basic CPUID: 0x%02x", cpu.highest_basic());
+	log::debug(logs::boot, "    Higest ext CPUID:   0x%02x", cpu.highest_ext() & ~cpu::cpu_id::cpuid_extended);
 
-#define CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit) \
-	if (leaf != feat_leaf || sub != feat_sub) { \
-		leaf = feat_leaf; sub = feat_sub; r = get(leaf, sub); \
-	} \
-	if (r.regname & (1ull << bit)) \
-		m_features |= (1ull << static_cast<uint64_t>(cpu_feature::name)); \
-	log::debug(logs::boot, "    Supports %9s: %s", #name, (r.regname & (1ull << bit)) ? "yes" : "no");
+#define CPU_FEATURE_OPT(name, ...) \
+	log::debug(logs::boot, "    Supports %9s: %s", #name, cpu.has_feature(cpu::feature::name) ? "yes" : "no");
 
 #define CPU_FEATURE_REQ(name, feat_leaf, feat_sub, regname, bit) \
 	CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit); \
-	if ((r.regname & (1ull << bit)) == 0) { \
-		log::error(logs::boot, "CPU missing required feature " #name); \
-		fail = true; \
-	}
+	kassert(cpu.has_feature(cpu::feature::name), "Missing required CPU feature " #name );
 
-#include "cpu_features.inc"
+#include "cpu/features.inc"
 #undef CPU_FEATURE_OPT
 #undef CPU_FEATURE_REQ
-
-	if (fail)
-		log::fatal(logs::boot, "CPU not supported.");
-}
-
-bool
-cpu_id::has_feature(cpu_feature feat)
-{
-	return (m_features & (1 << static_cast<uint64_t>(feat))) != 0;
 }
diff --git a/src/kernel/cpu.h b/src/kernel/cpu.h
index 84108fd..ed5722d 100644
--- a/src/kernel/cpu.h
+++ b/src/kernel/cpu.h
@@ -27,69 +27,6 @@ struct cpu_data
 
 extern cpu_data bsp_cpu_data;
 
-/// Enum of the cpu features jsix cares about
-enum class cpu_feature {
-#define CPU_FEATURE_REQ(name, ...)  name,
-#define CPU_FEATURE_OPT(name, ...)  name,
-#include "cpu_features.inc"
-#undef CPU_FEATURE_OPT
-#undef CPU_FEATURE_REQ
-	max
-};
-
-class cpu_id
-{
-public:
-	/// CPUID result register values
-	struct regs {
-		union {
-			uint32_t reg[4];
-			uint32_t eax, ebx, ecx, edx;
-		};
-
-		/// Return true if bit |bit| of EAX is set
-		bool eax_bit(unsigned bit) { return (eax >> bit) & 0x1; }
-
-		/// Return true if bit |bit| of EBX is set
-		bool ebx_bit(unsigned bit) { return (ebx >> bit) & 0x1; }
-
-		/// Return true if bit |bit| of ECX is set
-		bool ecx_bit(unsigned bit) { return (ecx >> bit) & 0x1; }
-
-		/// Return true if bit |bit| of EDX is set
-		bool edx_bit(unsigned bit) { return (edx >> bit) & 0x1; }
-	};
-
-	cpu_id();
-
-	/// The the result of a given CPUID leaf/subleaf
-	/// \arg leaf     The leaf selector (initial EAX)
-	/// \arg subleaf  The subleaf selector (initial ECX)
-	/// \returns      A |regs| struct of the values retuned
-	regs get(uint32_t leaf, uint32_t sub = 0) const;
-
-	/// Get the name of the cpu vendor (eg, "GenuineIntel")
-	inline const char * vendor_id() const	{ return m_vendor_id; }
-
-	/// Get the brand name of this processor model
-	inline const char * brand_name() const	{ return m_brand_name; }
-
-	/// Get the highest basic CPUID leaf supported
-	inline uint32_t highest_basic() const	{ return m_high_basic; }
-
-	/// Get the highest extended CPUID leaf supported
-	inline uint32_t highest_ext() const		{ return m_high_ext; }
-
-	/// Validate the CPU supports the necessary options for jsix
-	void validate();
-
-	/// Return true if the CPU claims to support the given feature
-	bool has_feature(cpu_feature feat);
-
-private:
-	uint32_t m_high_basic;
-	uint32_t m_high_ext;
-	char m_vendor_id[13];
-	char m_brand_name[48];
-	uint64_t m_features;
-};
+// We already validated the required options in the bootloader,
+// but iterate the options and log about them.
+void cpu_validate();
diff --git a/src/kernel/main.cpp b/src/kernel/main.cpp
index 6cd52f2..e872f1d 100644
--- a/src/kernel/main.cpp
+++ b/src/kernel/main.cpp
@@ -33,19 +33,10 @@ extern "C" {
 	void (*__ctors_end)(void);
 }
 
-void
-run_constructors()
-{
-	void (**p)(void) = &__ctors;
-	while (p < &__ctors_end) {
-		void (*ctor)(void) = *p++;
-		ctor();
-	}
-}
-
 extern void __kernel_assert(const char *, unsigned, const char *);
 
 /// Bootstrap the memory managers.
+void setup_pat();
 void memory_initialize_pre_ctors(kernel::args::header *kargs);
 void memory_initialize_post_ctors(kernel::args::header *kargs);
 
@@ -66,6 +57,16 @@ init_console()
 	cons->puts(GIT_VERSION " booting...\n");
 }
 
+void
+run_constructors()
+{
+	void (**p)(void) = &__ctors;
+	while (p < &__ctors_end) {
+		void (*ctor)(void) = *p++;
+		ctor();
+	}
+}
+
 channel *std_out = nullptr;
 
 void
@@ -110,9 +111,23 @@ void
 kernel_main(args::header *header)
 {
 	kutil::assert_set_callback(__kernel_assert);
+
 	init_console();
 	logger_init();
 
+	setup_pat();
+
+	bool has_video = false;
+	if (header->video.size > 0) {
+		has_video = true;
+		fb = memory::to_virtual<args::framebuffer>(reinterpret_cast<uintptr_t>(&header->video));
+
+		const args::framebuffer &video = header->video;
+		log::debug(logs::boot, "Framebuffer: %dx%d[%d] type %s @ %016llx",
+			video.horizontal, video.vertical, video.scanline, video.type, video.phys_addr);
+		logger_clear_immediate();
+	}
+
 	gdt_init();
 	interrupts_init();
 
@@ -120,8 +135,7 @@ kernel_main(args::header *header)
 	run_constructors();
 	memory_initialize_post_ctors(header);
 
-	cpu_id cpu;
-	cpu.validate();
+	cpu_validate();
 
 	for (size_t i = 0; i < header->num_modules; ++i) {
 		args::module &mod = header->modules[i];
@@ -135,13 +149,6 @@ kernel_main(args::header *header)
 		}
 	}
 
-	bool has_video = false;
-	if (header->video.size > 0) {
-		fb = memory::to_virtual<args::framebuffer>(reinterpret_cast<uintptr_t>(&header->video));
-		has_video = true;
-		logger_clear_immediate();
-	}
-
 	log::debug(logs::boot, "    jsix header is at: %016lx", header);
 	log::debug(logs::boot, "     Memory map is at: %016lx", header->mem_map);
 	log::debug(logs::boot, "ACPI root table is at: %016lx", header->acpi_table);
@@ -152,7 +159,6 @@ kernel_main(args::header *header)
 
 	interrupts_enable();
 	devices.init_drivers();
-
 	devices.get_lapic()->calibrate_timer();
 
 	/*
diff --git a/src/kernel/memory_bootstrap.cpp b/src/kernel/memory_bootstrap.cpp
index 114a5ce..df8d726 100644
--- a/src/kernel/memory_bootstrap.cpp
+++ b/src/kernel/memory_bootstrap.cpp
@@ -9,6 +9,7 @@
 #include "frame_allocator.h"
 #include "io.h"
 #include "log.h"
+#include "msr.h"
 #include "objects/process.h"
 #include "objects/vm_area.h"
 #include "vm_space.h"
@@ -100,6 +101,71 @@ void walk_page_table(
 }
 */
 
+static void
+log_mtrrs()
+{
+	uint64_t mtrrcap = rdmsr(msr::ia32_mtrrcap);
+	uint64_t mtrrdeftype = rdmsr(msr::ia32_mtrrdeftype);
+	unsigned vcap = mtrrcap & 0xff;
+	log::debug(logs::boot, "MTRRs: vcap=%d %s %s def=%02x %s %s",
+		vcap,
+		(mtrrcap & (1<< 8)) ? "fix" : "",
+		(mtrrcap & (1<<10)) ? "wc" : "",
+		mtrrdeftype & 0xff,
+		(mtrrdeftype & (1<<10)) ? "fe" : "",
+		(mtrrdeftype & (1<<11)) ? "enabled" : ""
+		);
+
+	for (unsigned i = 0; i < vcap; ++i) {
+		uint64_t base = rdmsr(find_mtrr(msr::ia32_mtrrphysbase, i));
+		uint64_t mask = rdmsr(find_mtrr(msr::ia32_mtrrphysmask, i));
+		log::debug(logs::boot, "       vcap[%2d] base:%016llx mask:%016llx type:%02x %s", i,
+			(base & ~0xfffull),
+			(mask & ~0xfffull),
+			(base & 0xff),
+			(mask & (1<<11)) ? "valid" : "");
+ 	}
+
+	msr mtrr_fixed[] = {
+		msr::ia32_mtrrfix64k_00000,
+		msr::ia32_mtrrfix16k_80000,
+		msr::ia32_mtrrfix16k_a0000,
+		msr::ia32_mtrrfix4k_c0000,
+		msr::ia32_mtrrfix4k_c8000,
+		msr::ia32_mtrrfix4k_d0000,
+		msr::ia32_mtrrfix4k_d8000,
+		msr::ia32_mtrrfix4k_e0000,
+		msr::ia32_mtrrfix4k_e8000,
+		msr::ia32_mtrrfix4k_f0000,
+		msr::ia32_mtrrfix4k_f8000,
+	};
+
+	for (int i = 0; i < 11; ++i) {
+		uint64_t v = rdmsr(mtrr_fixed[i]);
+		log::debug(logs::boot, "      fixed[%2d] %02x %02x %02x %02x %02x %02x %02x %02x", i,
+			((v <<  0) & 0xff), ((v <<  8) & 0xff), ((v << 16) & 0xff), ((v << 24) & 0xff),
+			((v << 32) & 0xff), ((v << 40) & 0xff), ((v << 48) & 0xff), ((v << 56) & 0xff));
+	}
+
+	uint64_t pat = rdmsr(msr::ia32_pat);
+	static const char *pat_names[] = {"UC ","WC ","XX ","XX ","WT ","WP ","WB ","UC-"};
+	log::debug(logs::boot, "      PAT: 0:%s 1:%s 2:%s 3:%s 4:%s 5:%s 6:%s 7:%s",
+		pat_names[(pat >> (0*8)) & 7], pat_names[(pat >> (1*8)) & 7],
+		pat_names[(pat >> (2*8)) & 7], pat_names[(pat >> (3*8)) & 7],
+		pat_names[(pat >> (4*8)) & 7], pat_names[(pat >> (5*8)) & 7],
+		pat_names[(pat >> (6*8)) & 7], pat_names[(pat >> (7*8)) & 7]);
+}
+
+void
+setup_pat()
+{
+	uint64_t pat = rdmsr(msr::ia32_pat);
+	pat = (pat & 0x00ffffffffffffffull) | (0x01ull << 56); // set PAT 7 to WC
+	wrmsr(msr::ia32_pat, pat);
+	log_mtrrs();
+}
+
+
 void
 memory_initialize_pre_ctors(args::header *kargs)
 {
diff --git a/src/kernel/msr.cpp b/src/kernel/msr.cpp
index d43c1fc..4efb175 100644
--- a/src/kernel/msr.cpp
+++ b/src/kernel/msr.cpp
@@ -1,5 +1,11 @@
 #include "msr.h"
 
+msr
+find_mtrr(msr type, unsigned index)
+{
+	return static_cast<msr>(static_cast<uint32_t>(type) + (2 * index));
+}
+
 uint64_t
 rdmsr(msr addr)
 {
diff --git a/src/kernel/msr.h b/src/kernel/msr.h
index 4d26425..ee02d45 100644
--- a/src/kernel/msr.h
+++ b/src/kernel/msr.h
@@ -6,22 +6,46 @@
 
 enum class msr : uint32_t
 {
-	ia32_efer			= 0xc0000080,
-	ia32_star			= 0xc0000081,
-	ia32_lstar			= 0xc0000082,
-	ia32_fmask			= 0xc0000084,
+	ia32_mtrrcap           = 0x000000fe,
+	ia32_mtrrdeftype       = 0x000002ff,
 
-	ia32_gs_base		= 0xc0000101,
-	ia32_kernel_gs_base = 0xc0000102
+	ia32_mtrrphysbase      = 0x00000200,
+	ia32_mtrrphysmask      = 0x00000201,
+
+	ia32_mtrrfix64k_00000  = 0x00000250,
+
+	ia32_mtrrfix16k_80000  = 0x00000258,
+	ia32_mtrrfix16k_a0000  = 0x00000259,
+
+	ia32_mtrrfix4k_c0000   = 0x00000268,
+	ia32_mtrrfix4k_c8000   = 0x00000269,
+	ia32_mtrrfix4k_d0000   = 0x0000026A,
+	ia32_mtrrfix4k_d8000   = 0x0000026B,
+	ia32_mtrrfix4k_e0000   = 0x0000026C,
+	ia32_mtrrfix4k_e8000   = 0x0000026D,
+	ia32_mtrrfix4k_f0000   = 0x0000026E,
+	ia32_mtrrfix4k_f8000   = 0x0000026F,
+
+	ia32_pat               = 0x00000277,
+	ia32_efer              = 0xc0000080,
+	ia32_star              = 0xc0000081,
+	ia32_lstar             = 0xc0000082,
+	ia32_fmask             = 0xc0000084,
+
+	ia32_gs_base           = 0xc0000101,
+	ia32_kernel_gs_base    = 0xc0000102
 };
 
+/// Find the msr for MTRR physical base or mask
+msr find_mtrr(msr type, unsigned index);
+
 /// Read the value of a MSR
-/// \arg addr   The MSR address
-/// \returns    The current value of the MSR
+/// \arg addr  The MSR address
+/// \returns   The current value of the MSR
 uint64_t rdmsr(msr addr);
 
 /// Write to a MSR
-/// \arg addr   The MSR address
-/// \arg value  The value to write
+/// \arg addr  The MSR address
+/// \arg value The value to write
 void wrmsr(msr addr, uint64_t value);
 
diff --git a/src/kernel/objects/vm_area.h b/src/kernel/objects/vm_area.h
index e8b34c2..dbeb18d 100644
--- a/src/kernel/objects/vm_area.h
+++ b/src/kernel/objects/vm_area.h
@@ -29,6 +29,7 @@ enum class vm_flags : uint32_t
 	huge_pages      = 0x00000200,
 
 	mmio            = 0x00010000,
+	write_combine   = 0x00020000,
 
 	user_mask       = 0x0000ffff  ///< flags allowed via syscall
 };
diff --git a/src/kernel/page_table.cpp b/src/kernel/page_table.cpp
index 5753e09..915493d 100644
--- a/src/kernel/page_table.cpp
+++ b/src/kernel/page_table.cpp
@@ -181,6 +181,7 @@ page_table::get_table_page()
 	s_page_cache = s_page_cache->next;
 	--s_cache_count;
 
+	kutil::memset(page, 0, memory::frame_size);
 	return reinterpret_cast<page_table*>(page);
 }
 
diff --git a/src/kernel/page_table.h b/src/kernel/page_table.h
index 5e3f010..8114f36 100644
--- a/src/kernel/page_table.h
+++ b/src/kernel/page_table.h
@@ -21,14 +21,21 @@ struct page_table
 		present   = 0x0001, /// Entry is present in the table
 		write     = 0x0002, /// Section may be written
 		user      = 0x0004, /// User-accessible
-		mtrr0     = 0x0008, /// MTRR selector bit 0
-		mtrr1     = 0x0010, /// MTRR selector bit 1
+		pat0      = 0x0008, /// PAT selector bit 0
+		pat1      = 0x0010, /// PAT selector bit 1
 		accessed  = 0x0020, /// Entry has been accessed
 		dirty     = 0x0040, /// Page has been written to
 		page      = 0x0080, /// Entry is a large page
-		pte_mtrr2 = 0x0080, /// MTRR selector bit 2 on PT entries
+		pat2      = 0x0080, /// PAT selector bit 2 on PT entries
 		global    = 0x0100, /// Entry is not PCID-specific
-		mtrr2     = 0x1000  /// MTRR selector bit 2 on PD and PDP entries
+		pat2_lg   = 0x1000, /// PAT selector bit 2 on large/huge pages
+
+		wb    = none,
+		wt    = pat0,
+		uc_   = pat1,
+		uc    = pat0 | pat1,
+		wc    = pat0 | pat1 | pat2,
+		wc_lg = pat0 | pat1 | pat2_lg,
 	};
 
 	/// Helper for getting the next level value
diff --git a/src/kernel/scheduler.cpp b/src/kernel/scheduler.cpp
index b8e203f..6ce2183 100644
--- a/src/kernel/scheduler.cpp
+++ b/src/kernel/scheduler.cpp
@@ -141,7 +141,7 @@ load_process_image(uintptr_t phys, uintptr_t virt, size_t bytes, TCB *tcb)
 
 	// Crazypants framebuffer part
 	if (fb) {
-		vma = new vm_area_open(fb->size, space, vm_flags::write|vm_flags::mmio);
+		vma = new vm_area_open(fb->size, space, vm_flags::write|vm_flags::mmio|vm_flags::write_combine);
 		space.add(0x100000000, vma);
 		vma->commit(fb->phys_addr, 0, memory::page_count(fb->size));
 	}
diff --git a/src/kernel/vm_space.cpp b/src/kernel/vm_space.cpp
index fd14f30..98fd6c9 100644
--- a/src/kernel/vm_space.cpp
+++ b/src/kernel/vm_space.cpp
@@ -170,7 +170,8 @@ vm_space::page_in(const vm_area &vma, uintptr_t offset, uintptr_t phys, size_t c
 	page_table::flag flags =
 		page_table::flag::present |
 		(m_kernel ? page_table::flag::none : page_table::flag::user) |
-		((vma.flags() && vm_flags::write) ? page_table::flag::write : page_table::flag::none);
+		((vma.flags() && vm_flags::write) ? page_table::flag::write : page_table::flag::none) |
+		((vma.flags() && vm_flags::write_combine) ? page_table::flag::wc : page_table::flag::none);
 
 	page_table::iterator it {virt, m_pml4};
 
diff --git a/src/libraries/cpu/cpu.cpp b/src/libraries/cpu/cpu.cpp
new file mode 100644
index 0000000..98395e5
--- /dev/null
+++ b/src/libraries/cpu/cpu.cpp
@@ -0,0 +1,97 @@
+#include <stdint.h>
+#include "cpu/cpu.h"
+
+namespace cpu {
+
+inline static void
+__cpuid(
+	uint32_t leaf,
+	uint32_t subleaf,
+	uint32_t *eax,
+	uint32_t *ebx = nullptr,
+	uint32_t *ecx = nullptr,
+	uint32_t *edx = nullptr)
+{
+	uint32_t a, b, c, d;
+	__asm__ __volatile__ ( "cpuid"
+			: "=a"(a), "=b"(b), "=c"(c), "=d"(d)
+			: "a"(leaf), "c"(subleaf)
+			);
+	if (eax) *eax = a;
+	if (ebx) *ebx = b;
+	if (ecx) *ecx = c;
+	if (edx) *edx = d;
+}
+
+cpu_id::cpu_id() :
+	m_features {0},
+	m_missing {0}
+{
+	__cpuid(0, 0,
+		&m_high_basic,
+		reinterpret_cast<uint32_t *>(&m_vendor_id[0]),
+		reinterpret_cast<uint32_t *>(&m_vendor_id[8]),
+		reinterpret_cast<uint32_t *>(&m_vendor_id[4]));
+
+	__cpuid(cpuid_extended, 0, &m_high_ext);
+
+	if (m_high_ext >= cpuid_extended + 4) {
+		__cpuid(cpuid_extended + 2, 0,
+			reinterpret_cast<uint32_t *>(&m_brand_name[0]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[4]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[8]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[12]));
+		__cpuid(cpuid_extended + 3, 0,
+			reinterpret_cast<uint32_t *>(&m_brand_name[16]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[20]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[24]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[28]));
+		__cpuid(cpuid_extended + 4, 0,
+			reinterpret_cast<uint32_t *>(&m_brand_name[32]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[36]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[40]),
+			reinterpret_cast<uint32_t *>(&m_brand_name[44]));
+	} else {
+		m_brand_name[0] = 0;
+	}
+
+	uint32_t leaf = -1u;
+	uint32_t sub = -1u;
+	regs r;
+#define CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit) \
+	if (leaf != feat_leaf || sub != feat_sub) { \
+		leaf = feat_leaf; sub = feat_sub; r = get(leaf, sub); \
+	} \
+	if (r.regname & (1ull << bit)) \
+		m_features |= (1ull << static_cast<uint64_t>(feature::name)); \
+
+#define CPU_FEATURE_REQ(name, feat_leaf, feat_sub, regname, bit) \
+	CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit); \
+	if ((r.regname & (1ull << bit)) == 0) { \
+		m_missing |= (1ull << static_cast<uint64_t>(feature::name)); \
+	}
+
+#include "cpu/features.inc"
+#undef CPU_FEATURE_OPT
+#undef CPU_FEATURE_REQ
+}
+
+cpu_id::regs
+cpu_id::get(uint32_t leaf, uint32_t sub) const
+{
+	regs ret {0, 0, 0, 0};
+
+	if ((leaf & cpuid_extended) == 0 && leaf > m_high_basic) return ret;
+	if ((leaf & cpuid_extended) != 0 && leaf > m_high_ext) return ret;
+
+	__cpuid(leaf, sub, &ret.eax, &ret.ebx, &ret.ecx, &ret.edx);
+	return ret;
+}
+
+bool
+cpu_id::has_feature(feature feat)
+{
+	return (m_features & (1 << static_cast<uint64_t>(feat))) != 0;
+}
+
+}
diff --git a/src/libraries/cpu/include/cpu/cpu.h b/src/libraries/cpu/include/cpu/cpu.h
new file mode 100644
index 0000000..ceace0f
--- /dev/null
+++ b/src/libraries/cpu/include/cpu/cpu.h
@@ -0,0 +1,81 @@
+#pragma once
+/// \file cpu.h Definition of required cpu features for jsix
+
+#include <stdint.h>
+
+namespace cpu {
+
+/// Enum of the cpu features jsix cares about
+enum class feature {
+#define CPU_FEATURE_REQ(name, ...)  name,
+#define CPU_FEATURE_OPT(name, ...)  name,
+#include "cpu/features.inc"
+#undef CPU_FEATURE_OPT
+#undef CPU_FEATURE_REQ
+	max
+};
+
+class cpu_id
+{
+public:
+	static constexpr uint32_t cpuid_extended = 0x80000000;
+
+	/// CPUID result register values
+	struct regs {
+		union {
+			uint32_t reg[4];
+			uint32_t eax, ebx, ecx, edx;
+		};
+
+		/// Return true if bit |bit| of EAX is set
+		bool eax_bit(unsigned bit) { return (eax >> bit) & 0x1; }
+
+		/// Return true if bit |bit| of EBX is set
+		bool ebx_bit(unsigned bit) { return (ebx >> bit) & 0x1; }
+
+		/// Return true if bit |bit| of ECX is set
+		bool ecx_bit(unsigned bit) { return (ecx >> bit) & 0x1; }
+
+		/// Return true if bit |bit| of EDX is set
+		bool edx_bit(unsigned bit) { return (edx >> bit) & 0x1; }
+	};
+
+	cpu_id();
+
+	/// The the result of a given CPUID leaf/subleaf
+	/// \arg leaf     The leaf selector (initial EAX)
+	/// \arg subleaf  The subleaf selector (initial ECX)
+	/// \returns      A |regs| struct of the values retuned
+	regs get(uint32_t leaf, uint32_t sub = 0) const;
+
+	/// Get the name of the cpu vendor (eg, "GenuineIntel")
+	inline const char * vendor_id() const	{ return m_vendor_id; }
+
+	/// Get the brand name of this processor model
+	inline const char * brand_name() const	{ return m_brand_name; }
+
+	/// Get the highest basic CPUID leaf supported
+	inline uint32_t highest_basic() const	{ return m_high_basic; }
+
+	/// Get the highest extended CPUID leaf supported
+	inline uint32_t highest_ext() const		{ return m_high_ext; }
+
+	/// Get which required options are missing as flags
+	inline uint64_t missing() const         { return m_missing; }
+
+	/// Validate the CPU supports the necessary options for jsix
+	inline bool supported() const           { return m_missing; }
+
+	/// Return true if the CPU claims to support the given feature
+	bool has_feature(feature feat);
+
+private:
+	uint32_t m_high_basic;
+	uint32_t m_high_ext;
+	uint64_t m_features;
+	uint64_t m_missing;
+	char m_vendor_id[13];
+	char m_brand_name[48];
+};
+
+}
diff --git a/src/kernel/cpu_features.inc b/src/libraries/cpu/include/cpu/features.inc
similarity index 89%
rename from src/kernel/cpu_features.inc
rename to src/libraries/cpu/include/cpu/features.inc
index b455f53..34d3f54 100644
--- a/src/kernel/cpu_features.inc
+++ b/src/libraries/cpu/include/cpu/features.inc
@@ -7,8 +7,9 @@ CPU_FEATURE_REQ(pse,        0x00000001, 0, edx,  3)
 CPU_FEATURE_OPT(tsc,        0x00000001, 0, edx,  4)
 CPU_FEATURE_REQ(msr,        0x00000001, 0, edx,  5)
 CPU_FEATURE_REQ(apic,       0x00000001, 0, edx,  9)
+CPU_FEATURE_REQ(mtrr,       0x00000001, 0, edx, 12)
 CPU_FEATURE_REQ(pge,        0x00000001, 0, edx, 13)
-CPU_FEATURE_OPT(pat,        0x00000001, 0, edx, 16)
+CPU_FEATURE_REQ(pat,        0x00000001, 0, edx, 16)
 CPU_FEATURE_REQ(fxsr,       0x00000001, 0, edx, 24)
 
 CPU_FEATURE_OPT(fsgsbase,   0x00000007, 0, ebx,  0)
diff --git a/src/libraries/libc/string/memcpy.c b/src/libraries/libc/string/memcpy.c
index 981d3c6..ed1cda9 100644
--- a/src/libraries/libc/string/memcpy.c
+++ b/src/libraries/libc/string/memcpy.c
@@ -10,9 +10,24 @@ void * memcpy( void * restrict s1, const void * restrict s2, size_t n )
 {
     char * dest = (char *) s1;
     const char * src = (const char *) s2;
-    while ( n-- )
-    {
+
+	if (((uintptr_t)src & 7) == ((uintptr_t)dest & 7)) {
+		while (((uintptr_t)src & 7) && n--)
+			*dest++ = *src++;
+
+		const uint64_t *srcq = (const uint64_t*)src;
+		uint64_t *destq = (uint64_t*)dest;
+		while (n >= 8) {
+			*destq++ = *srcq++;
+			n -= 8;
+		}
+
+		src = (const char*)srcq;
+		dest = (char*)destq;
+	}
+
+    while (n--)
         *dest++ = *src++;
-    }
+
     return s1;
 }