1CPUID(1) General Commands Manual CPUID(1)
2
6 cpuid - Dump CPUID information for each CPU
7
9 cpuid [options...]
10
12 cpuid dumps detailed information about the CPU(s) gathered from the
13 CPUID instruction, and also determines the exact model of CPU(s) from
14 that information.
15 It dumps all information available from the CPUID instruction. The
17 exact collection of information available varies between manufacturers
18 and processors. The following information is available consistently on
19 all modern CPUs:
20 vendor_id
22 version information (1/eax)
23 miscellaneous (1/ebx)
24 feature information (1/ecx)
25 It also produces synthetic fields based on information from multiple
27 CPUID functions. Currently, the synthetic fields are the exact model
28 of each CPU (but see LIMITATIONS below) as (synth); the multiprocessing
29 characteristics including the number of cores per chip (c) and the num‐
30 ber of hyperthreads per core (t) as (multi-processing synth); and a
31 decoding of the APIC physical ID as (APIC synth).
32 The determination of the model is based on the following information:
34 version information (1/eax), processor type
36 version information (1/eax), family
37 version information (1/eax), model
38 version information (1/eax), stepping id
39 version information (1/eax), extended family
40 version information (1/eax), extended model
41 feature information (1/ecx), virtual machine extensions
42 brand id (1/ebx)
43 brand (0x80000004)
44 cache and TLB information (2)
45 deterministic cache parameters (4/eax), extra processor cores
46 AMD extended brand id (0x80000001/ebx)
47 AMD extended processor signature (0x80000001/eax)
48 Transmeta processor revision ID (0x80860001/ebx & ecx)
49 The determination of the multiprocessing characteristics and decoding
51 of APIC physical ID is based on the following information:
52 feature information (1/edx), hyper-threading / multi-core supported
54 miscellaneous (1/ebx), cpu count
55 deterministic cache parameters (4/eax), extra processor cores on this die
56 x2APIC features / processor topology (0xb)
57 AMD feature flags (0x80000001/ecx)
58 AMD Logical CPU cores (0x80000008/ecx), number of logical CPU cores - 1
59 In addition, a simpler and coarser determination of the CPU is per‐
61 formed using only the information listed above under version informa‐
62 tion (1/eax). It is provided as (simple synth) under version informa‐
63 tion (1/eax). However, it tends to be unable to distinguish between
64 various modern CPUs.
65
67 cpuid accepts the following command line arguments:
68 -1, --one-cpu
70 Display information only for the first CPU. This cuts down on
71 the output on a multiprocessor system, and is useful when cer‐
72 tain that all CPUs are identical.
73 -f FILE, --file=FILE
75 Read raw hex information from FILE instead of from executions
76 of the cpuid instruction. If the filename is '-', instead read
77 from standard input.
78 -h, -H, --help
80 Display help information.
81 -i, --inst
83 Use the CPUID instruction. The information it provides is
84 reliable. It is not necessary to be root to use this option.
85 (This option is the default.)
86 -k, --kernel
88 Use the CPUID kernel module. The information does not seem to
89 be reliable on all combinations of CPU type and kernel version.
90 Typically, it is necessary to be root to use this option.
91 -r, --raw
93 Display only raw hex information with no decoding.
94 -v, --version
96 Display cpuid version.
97
99 There are numerous cases where there is no way to distinguish between
100 various CPUs in the (synth) information. In some cases, the sizes of
101 caches, number of cores, brand strings, etc., can be used to distin‐
102 guish multiple CPUs with the same family and model. But there are
103 cases where that information is insufficient. Whenever cpuid is unable
104 to distinguish between multiple CPUs, it will list all known possibili‐
105 ties.
106 If you believe that a certain processor should be distinguishable from
108 another and it isn't, please inform the author of this tool.
109 The (multi-processing synth) information is unreliable on many proces‐
111 sors. It faithfully reports the information provided by the CPUID
112 instruction and decodes it as recommended by the processor manufactur‐
113 ers, but often that information is incorrect. The information seems to
114 indicate the architecture's capabilities, rather than what the particu‐
115 lar chip actually does. In particular, it seems commonplace to claim
116 the presence of multiple hyperthreads when there is only one.
117
119 Information on the CPUID instruction and on specific CPUs is available
120 from the following documents from Intel Corporation
121 <http://www.intel.com/support/processors/index.htm>, with the specified
122 Document Numbers:
123 241618: Intel Processor Identification and the CPUID Instruc‐
125 tion, Application Note 485
126 242480: Pentium Processor Specification Update
127 242689: Pentium Pro Processor Specification Update
128 243326: 60- and 66-MHz Pentium Processor Specification Update
129 243337: Intel Pentium II Processor Specification Update
130 243748: Intel Celeron Processor Specification Update
131 243776: Intel Pentium II Xeon Processor Specification Update
132 243887: Mobile Intel Pentium II Processor Specification Update
133 244444: Mobile Intel Celeron Processor at 466 MHz, 433 MHz, 400
134 MHz, 366 MHz, 333 MHz, 300 MHz, and 266 MHz Specification Update
135 244453: Intel Pentium III Processor Specification Update
136 244460: Intel Pentium III Xeon Processor Specification Update
137 245306: Mobile Intel Pentium III Processor and Mobile Intel Pen‐
138 tium III Processor-M Specification Update
139 245421: Mobile Intel Celeron Processor (0.18u and 0.13u) Speci‐
140 fication Update
141 249199: Intel Pentium 4 Processor Specification Update
142 249678: Intel Xeon Processor Specification Update
143 250721: Mobile Intel Pentium 4 Processor-M Specification Update
144 251309: Mobile Intel Celeron Processor on .13 Micron Process in
145 Micro-FCPGA Package Specification Update
146 252665: Intel Pentium M Processor Specification Update
147 253176: Mobile Intel Pentium 4 Processor with 533 MHz System Bus
148 Specification Update
149 253666: 64 and IA-32 Architectures Software Developer's Manual
150 Volume 2A: Instruction Set Reference, A-M.
151 276613: Detecting Multi-Core Processor Topology in an IA-32
152 Platform by Khang Nguyen and Shihjong Kuo
153 290741: Intel Xeon Processor MP Specification Update
154 290749: Intel Celeron Processor in the 478-Pin Package Specifi‐
155 cation Update
156 300303: Intel Celeron M Processor Specification Update
157 302209: Intel Pentium M Processor on 90nm Process with 2-MB L2
158 Cache Specification Update
159 302352: Intel Pentium 4 Processor on 90 nm Process Specification
160 Update
161 302354: Intel Celeron D Processor 3xx Sequence Specification
162 Update
163 302402: Intel Xeon Processor with 800 MHz System Bus
164 302441: Mobile Intel Pentium 4 Processor supporting Hyper-
165 Threading Technology on 90-nm process technology Specification
166 Update
167 306752: 64-bit Intel Xeon Processor MP with 1 MB L2 Cache Speci‐
168 fication Update
169 306757: 64-bit Intel Xeon Processor MP with up to 8 MB L3 Cache
170 Specification Update
171 306832: Intel Pentium Processor Extreme Edition and Intel Pen‐
172 tium D Processor Specification Update
173 309159: Dual-Core Intel Xeon Processor 2.80 GHz Specification
174 Update
175 309222: Intel Core Duo Processor and Intel Core Solo Processor
176 on 65 nm Process Specification Update
177 309627: Dual-Core Intel Xeon Processor 7000 Sequence Specifica‐
178 tion Update
179 311827: Intel Celeron D Processor 300 Sequence Specification
180 Update
181 313065: Dual-Core Intel Xeon Processor 5000 Series Specification
182 Update
183 313279: Intel Core 2 Extreme Processor X6800 and Intel Core 2
184 Duo Desktop Processor E6000 Sequence Specification Update
185 313356: Dual-Core Intel Xeon Processor 5100 Series Specification
186 Update
187 314554: Dual-Core Intel Xeon Processor 7100 Series Specification
188 Update
189 314916: Dual-Core Intel Xeon Processor 3000 Series Specification
190 Update
191 313515: Intel Pentium Dual-Core Processor Specification Update
192 316134: Quad-Core Intel Xeon Processor 3200 Series Specification
193 Update
194 316964: Intel Celeron Processor 400 Series Specification Update
195 316982: Intel Pentium Dual-Core Desktop Processor E2000 Series
196 Specification Update
197 317667: Intel Celeron Processor 500 Series Specification Update
198 318081: Intel Xeon Processor 7200 and 7300 Series Specification
199 Update
200 318547: Intel Celeron Processor 200 Sequence Specification
201 Update
202 318585: Intel Xeon Processor 5400 Series Specification Update
203 318586: Intel Xeon Processor 5200 Series Specification Update
204 318727: Intel Core 2 Extreme Processor QX9000 Series and Intel
205 Core 2 Quad Processor Q9000, Q9000S, Q8000, Q8000S Series Speci‐
206 fication Update
207 318733: Intel Core 2 Duo Processor E8000 and E7000 Series Speci‐
208 fication Update
209 318915: Intel Core 2 Duo Processor and Intel Core 2 Extreme Pro‐
210 cessor on 45-nm Process Specification Update
211 318925: Intel Celeron Dual-Core Processor E1000 Series Specifi‐
212 cation Update
213 319006: Dual-Core Intel Xeon Processor 3100 Series Specification
214 Update
215 319007: Quad-Core Intel Xeon Processor 3300 Series Specification
216 Update
217 319129: Intel Core 2 Extreme Processor QX9775 Specification
218 Update
219 319433: Intel Architecture Instruction Set Extensions Program‐
220 ming Reference
221 319536: Intel Atom Processor Z5xx Series Specification Update
222 319735: Intel Celeron Dual-Core Processor T1x00 Series Specifi‐
223 cation Update
224 319978: Intel Atom Processor 200 Series Specification Update
225 320047: Intel Atom Processor N270 Series Specification Update
226 320121: Intel Core 2 Extreme Quad-Core Mobile Processor, Intel
227 Core 2 Quad Mobile Processor, Intel Core 2 Extreme Mobile Pro‐
228 cessor, Intel Core 2 Duo Mobile Processor, Intel Core 2 Solo
229 Mobile Processor and Intel Celeron Processor on 45-nm Process
230 Specification Update
231 320257: Intel EP80579 Integrated Processor Product Line Specifi‐
232 cation Update
233 320336: Intel Xeon Processor 7400 Series Specification Update
234 320468: Intel Pentium Dual-Core E6000 and E5000 Series Specifi‐
235 cation Update
236 320529: Intel Atom Processor 300 Series Specification Update
237 320767: Intel Core i7-900 Mobile Processor Extreme Edition
238 Series, Intel Core i7-800 and i7-700 Mobile Processor Series
239 Specification Update
240 320836: Intel Core i7-900 Desktop Processor Extreme Edition
241 Series and Intel Core i7-900 Desktop Processor Series Specifica‐
242 tion Update
243 321324: Intel Xeon Processor 5500 Series Specification Update
244 321333: Intel Xeon Processor 3500 Series Specification Update
245 322166: Intel Core i7-800 and i5-700 Desktop Processor Series
246 Specification Update
247 322373: Intel Xeon Processor 3400 Series Specification Update
248 322568: Intel Celeron Processor E3x00 Series Specification
249 Update
250 322849: Intel Atom Processor N400 Series Specification Update
251 322861: Intel Atom Processor D400 Series (Single Core) Specifi‐
252 cation Update
253 322862: Intel Atom Processor D500 Series (Dual Core) Specifica‐
254 tion Update
255 322814: Intel Core i7-600, i5-500, i5-400 and i3-300 Mobile Pro‐
256 cessor Series Specification Update
257 322911: Intel Core i5-600, i3-500 Desktop Processor Series and
258 Intel Pentium Processor G6950 Specification Update
259 323056: Intel Xeon Processor L3406 Specification Update
260 323179: Intel Core i7-660UE, i7-620LE/UE, i7-610E, i5-520E,
261 i3-330E and Intel Celeron Processor P4505, U3405 Series
262 Datasheet Addendum Specification Update
263 323105: Intel Xeon Processor C5500/C3500 Series Specification
264 Update
265 323254: Intel Core i7-900 Desktop Processor Extreme Edition
266 Series and Intel Core i7-900 Desktop Processor Series on 32-nm
267 Process Specification Update
268 323338: Intel Xeon Processor 3600 Series Specification Update
269 323344: Intel Xeon Processor 7500 Series Specification Update
270 323372: Intel Xeon Processor 5600 Series Specification Update
271 323874: Intel Pentium P6000 and U5000 Mobile Processor Series
272 Specification Update
273 324209: Intel Atom Processor E6xx Series Specification Update
274 324341: Intel Atom Processor N500 Series Specification Update
275 Intel 64 Architecture Processor Topology Enumeration (Whitepa‐
276 per) by Shih Kuo
277 324456: Intel Celeron Mobile Processor P4000 and U3000 Series
278 Specification Update
279 324643: 2nd Generation Intel Core Processor Family Desktop Spec‐
280 ification Update
281 324827: 2nd Generation Intel Core Processor Family Mobile Speci‐
282 fication Update
283 325122: Intel Xeon Processor E7-8800 / 4800 / 2800 Product Fami‐
284 lies Specification Update
285 325307: Intel Atom Processor Z600 Series Specification Update
286 325462: Intel 64 and IA-32 Architectures Software Developer's
287 Manual Combined Volumes: 1, 2A, 2B, 2C, 3A, 3B, and 3C
288 325630: Intel Atom Processor Z6xx Series Specification Update
289 326140: Intel Atom Processor N2000 and D2000 Series Specifica‐
290 tion Update
291 326198: Intel Core i7 Processor Family for the LGA-2011 Socket
292 Specification Update
293 326510: Intel Xeon Processor E5 Family Specification Update
294 326766: Desktop 3rd Generation Intel Core Processor Family Spec‐
295 ification Update
296 326770: Mobile 3rd Generation Intel Core Processor Family Speci‐
297 fication Update
298 326774: Intel Xeon Processor E3-1200 v2 Product Family Specifi‐
299 cation Update
300 327335: Intel Xeon and Intel Core Processors For Communications
301 Infrastructure Specification Update
302 328105: Intel Atom Processor Z2760 Specification Update
303 328198: Intel Atom Processor S1200 Product Family for
304 Microserver Specification Update
305 328205: Intel Xeon Phi Coprocessor x100 Product Family Specifi‐
306 cation Update
307 328899: Desktop 4th Generation Intel Core Processor Family Spec‐
308 ification Update
309 328903: Mobile 4th Generation Intel Core Processor Family Speci‐
310 fication Update
311 328908: Intel Xeon Processor E3-1200 v3 Product Family Specifi‐
312 cation Update
313 329376: Intel Xeon E3-1125C v2, E3-1105C v2, Intel Core 3115C
314 and Intel Pentium Processor B925C Specification Update
315 329460: Intel Atom Processor C2000 Product Family Specification
316 Update
317 329597: Intel Xeon Processor E7 v2 Product Family Specification
318 Update
319 329676: Intel Quark SoC X1000 Datasheet
320 330785: Intel Xeon Processor E5 v3 Product Family Specification
321 Update
322 330836: 5th Generation Intel Core Processor Family, Intel Core M
323 Processor Family, Mobile Intel Pentium Processor Family, and
324 Mobile Intel Celeron Processor Family Specification Update
325 330841: Intel Core i7 Processor Family for LGA2011-v3 Socket
326 Specification Update
327 332054: Intel Xeon Processor D-1500 Product Family Specification
328 Update
329 332067: Intel Atom Z8000 Processor Series Specification Update
330 332095: Intel N-Series Intel Pentium Processors and Intel
331 Celeron Processors Specification Update
332 332317: Intel Xeon Processor E7 v3 Product Family Specification
333 Update
334 332381: Mobile/Desktop 5th Generation Intel Core Processor Fam‐
335 ily Specification Update
336 332689: 6th Generation Intel Core Processor Family Specification
337 Update
338 333133: Intel Xeon Processor E3-1200 v5 Product Family Specifi‐
339 cation Update
340 333811: Intel Xeon Processor E5-2600 v4 Product Family Specifi‐
341 cation Update
342 334165: Intel Xeon Processor E7-8800/4800 v4 Product Family
343 Specification Update
344 334208: Intel Core i7 Processor Family for LGA2011-v3 Socket
345 Specification Update
346 334525: Control-flow Enforcement Technology Preview
347 334646: Intel Xeon Phi Processor x200 Product Family Preliminary
348 Specification Update
349 334663: 7th Generation Intel Processor Family Specification
350 Update Supporting 7th Generation Intel Core Processor Families
351 based on U/Y-Processor Line
352 334820: Intel Pentium and Celeron Processor N- and J- Series
353 Specification Update
354 335252: 5-Level Paging and 5-Level EPT White Paper
355 335718: Intel Xeon Processor E3-1200 v6 Product Family Specifi‐
356 cation Update
357 335901: Intel Core X-Series Processor Family Specification
358 Update
359 336466: 8th Generation Intel Processor Family for S-Processor
360 Platforms Specification Update
361 336505: Intel Xeon Processor Scalable Family Specification
362 Update
363 336562: Intel Pentium Silver and Intel Celeron Processors Speci‐
364 fication Update
365 Information on the CPUID instruction and on specific CPUs is available
367 from the following documents from Advanced Micro Devices, Inc.
368 <http://www.amd.com/us-en/Processors/TechnicalResources>, with the
369 specified Publication Numbers:
370 20734: AMD Processor Recognition Application Note
372 21266: AMD-K6 Processor Revision Guide Model 6
373 21641: AMD-K6-2 Processor Revision Guide Model 8
374 21846: AMD-K6 Processor Revision Guide Model 7
375 22473: AMD-K6-III Processor Revision Guide Model 9
376 23614: AMD Athlon Processor Model 4 Revision Guide
377 23865: AMD Duron Processor Model 3 Revision Guide
378 24332: AMD Athlon Processor Model 6 Revision Guide
379 24806: AMD Duron Processor Model 7 Revision Guide
380 25481: CPUID Specification
381 25703: AMD Athlon Processor Model 8 Revision Guide
382 25759: Revision Guide for AMD Athlon 64 and AMD Opteron Proces‐
383 sors
384 26094: BIOS and Kernel Developer's Guide for AMD Athlon 64 and
385 AMD Opteron Processors
386 27532: AMD Athlon Processor Model 10 Revision Guide
387 31177H: AMD Geode NX Processors Data Book
388 31610: Revision Guide for AMD NPT Family 0Fh Processors
389 33234F: AMD Geode LX Processors Data Book
390 41322: Revision Guide for AMD Family 10h Processors
391 41788: Revision Guide for AMD Family 11h Processors
392 44739: Revision Guide for AMD Family 12h Processors
393 47534: Revision Guide for AMD Family 14h Models 00h-0Fh Proces‐
394 sors
395 48063: Revision Guide for AMD Family 15h Models 00h-0Fh Proces‐
396 sors
397 48931: Revision Guide for AMD Family 15h Models 10h-1Fh Proces‐
398 sors
399 51603: Revision Guide for AMD Family 15h Models 30h-3Fh Proces‐
400 sors
401 51810: Revision Guide for AMD Family 16h Models 00h-0Fh Proces‐
402 sors
403 53072: Revision Guide for AMD Family 16h Models 30h-3Fh Proces‐
404 sors
405 54945: Processor Programming Reference (PPR) for AMD Family 17h
406 Model 01h, Revision B1 Processors
407 55370: Revision Guide for AMD Family 15h Models 70h-7Fh Proces‐
408 sors
409 55766: Secure Encrypted Virtualization API Version 0.16 Techni‐
410 cal Preview
411 Information on the CPUID instruction and on specific CPUs is available
413 from the following documents from Transmeta Corporation
414 <http://www.transmeta.com/crusoe_docs/Crusoe_CPUID_5-7-02.pdf>:
415 Processor Recognition, 2002/05/07
417 Information on generic hypervisor CPUID levels is available from this
419 proposal: <http://lwn.net/Articles/301888/>.
420 Information on KVM hypervisor CPUID levels is available from the Linux
422 kernel under Documentation/kvm/cpuid.txt.
423 Information on Microsoft hypervisor CPUID levels is available from the
425 following documents from Microsoft: <https://docs.microsoft.com/en-
426 us/virtualization/hyper-v-on-windows/reference/tlfs> and
427 <http://msdn.microsoft.com/en-us/library/windows/hard‐
428 ware/ff542428%28v=vs.85%29.aspx>.
429 Also, information is available from the following web sites:
431 <http://www.sandpile.org/ia32/cpuid.htm>
433 <http://en.wikipedia.org/wiki/List_of_Intel_microprocessors>
434 <http://en.wikipedia.org/wiki/List_of_AMD_microprocessors>
435 <http://en.wikipedia.org/wiki/Category:X86_microprocessors>
436
438 Todd Allen <cpuid@etallen.com>
43920180519 19 May 2018 CPUID(1)