I recently purchased a processor off eBay that was labelled as an Intel Core i5-2520M. It came shipped in just a tray, not the original box, but the processor and all its markings look perfectly legitimate.

My system BIOS reports it as a Genuine Intel(R) CPU 0 @ 2.50GHz and shows the CPU-ID as 206A5, which, when I stick it into Google, turns up the Intel Core i7-2720qm instead.

The CPU seems to work fine for the most part and runs Windows 8 64-bit without issues, although it is giving me some trouble with AMT, but I'm not sure whether this is a CPU or a motherboard issue.

So, this leaves me with a couple of questions:

  • Is it possible to update the microcode of a CPU to pass it off as a different one?
  • Is it normal that a genuine CPU gets reported as "CPU 0" in the BIOS rather than its actual ID?
  • Could this chip be an engineering sample?
  • Is there a software tool that will check whether a processor is genuine?

I ran CPU-Z and it reports the following:

Name           Intel Core i5 2450M (hmmm...)
Code Name      Sandy Bridge
Max TDP        35 W
Package        Socket 988B rPGA
Technology     32 nm
Core Voltage   0.792 V
Specification  Genuine Intel(R) CPU 0 @ 2.5 GHz (ES)
Family         6
Ext. Family    6
Model          A
Ext. Model     2A
Stepping       5
Revision       D0
Instructions   MMX,SSE,SSE2,SSE3,SSSE3,SSE4.1,SSE4.2,EM64T,VT-x,AES,AVX

Should it look like this for a 2520M CPU?

  • 3
    what're you using for the information? On the off chance someone has the same processor, you might be able to check with them. I'm also wondering, since this is a mobile chip, it might be some bios/firmware wierdness with the motherboard. The big difference between a core i7 and a core i5 of the same generation would be the l3 cache, and you can check that - the processor you think you have has 4mb, and the other has 6 I believe
    – Journeyman Geek
    Aug 23, 2013 at 2:55
  • Mind running cpuz and showing what it reports? cpuid.com/softwares/cpu-z/versions-history.html
    – spuder
    Aug 23, 2013 at 2:56
  • hmm prd1glbser.cps.intel.com/gserial/home.aspx might be of use, you can use the ULT number to try to work out more details on it.
    – Journeyman Geek
    Aug 23, 2013 at 3:07
  • 5
    "CPU 0" would be the number of the CPU in the system (i.e. the first CPU enumerated). Aug 23, 2013 at 7:06
  • 1
    Intel doesn't sell mobile CPUs in retail boxes anyway, only in trays. Only desktop and server CPUs are sold in both boxes and trays. Feb 10, 2015 at 4:35

4 Answers 4


It's an engineering sample (emphasis added):

Specification Genuine Intel(R) CPU 0 @ 2.5GHz (ES)

For more information, see this Intel page: Information about Intel Engineering/Qualification Sample Processors

  • 2
    heh, I missed that, despite explictly mentioning engineering samples in my answer. Its the little things ;p
    – Journeyman Geek
    Aug 23, 2013 at 3:30
  • 2
    Yep, you're correct. It's an engineering sample. After looking again, it even said so on the ebay sales page in the fine print... Thanks for the link, too. Good to know! +1 √ :)
    – Markus A.
    Aug 23, 2013 at 3:32
  • 2
    electronics.stackexchange.com/questions/48738/… entirely relevant. Annoyingly, I was looking at this and didn't make the connection ;p
    – Journeyman Geek
    Aug 23, 2013 at 3:39
  • 1
    good if you want to collect things. They are rarely available. On the other hand not suitable for production. Until everything works, you can use it at home for gaming. :C)
    – Dee
    Aug 23, 2013 at 10:26

Well, you got shipped a newer processor than what you ordered, with a marginally lower clockspeed and a few features disabled. Unless it was a hell of a deal, you might want to yell at the ebay vendor.

To sum up all the things in the comments and a few extra details - various levels of fake processors exist from repacked engineering sample chips, to the lovely, and utterly non functional core i7 920 newegg accidentally shipped a few years ago. You'd notice these are repacked chips, or complete bricks, rather than cunningly modified, or homebrewed processors.

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In this case though, you got a newer core i5 2450 rather than an older, slightly faster 2520 which has a few additional features. While some intel processors can be softmodded to unlock additional cache and features, I couldn't find any reference to radical softmodding. While you didn't get what you paid for, the chip you have is probably as it was designed and manufactured by intel. I'd suggest taking a closer look at those chip markings - since they would confirm it. It would be possible, and a little crafty to swap those heatshields, but its unlikely since its too much work.

The product identification utility by intel might be of interest here as well

  • 2
    Unfortunately it was exactly those features (Vt-d and vPro) that I was trying to get... It's for a server build...
    – Markus A.
    Aug 23, 2013 at 3:40
  • with a mobile processor?
    – Journeyman Geek
    Aug 23, 2013 at 3:41
  • 1
    Just needs to run an encrypted RAID... this way it's easy on the power consumption and since it supports vPro, Vt-d and AES-NI, it has all the hardware features and acceleration I need... :)
    – Markus A.
    Aug 23, 2013 at 3:55
  • @JourneymanGeek for anyone looking these days, some others you see occasionally now are BGA CPUs fitted with sockets, and sometimes a Chinese x86 CPU rebranded as an Intel (and I'm sure AMD) CPU.
    – Levi H
    Sep 5, 2020 at 19:22

As noted by DragonLord, the CPU I purchased on ebay is an Engineering Sample.

I have meanwhile received a replacement processor that is actually a genuine Core Intel i5-2520M.

Here are the differences:

  1. This one, the system BIOS identifies correctly as an

    Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz

    with CPU-ID 206A7.

    So, the CPU 0 part of Genuine Intel(R) CPU 0 was actually NOT an indication that this is the first CPU in the system (as suspected in some answers/comments here), but really part of the CPU-ID given by Intel for this particular (and maybe all) Engineering Sample CPU.

  2. CPU-Z now reports (differences marked):

    -> Name           Intel Core i5 2520M
       Code Name      Sandy Bridge
       Max TDP        35W
       Package        Socket 988B rPGA
       Technology     32nm
       Core Voltage   0.752V
    -> Specification  Intel(R) Core(TM) i5-2520M CPU @ 2.5GHz
       Family         6
       Ext. Family    6
       Model          A
       Ext. Model     2A
    -> Stepping       7
    -> Revision       D2
       Instructions   MMX,SSE,SSE2,SSE3,SSSE3,SSE4.1,SSE4.2,EM64T,VT-x,AES,AVX

    (I didn't mark the Core Voltage as different since it keeps fluctuating a bit anyways)

  3. What do you know? AMT now works perfectly!

I will leave DragonLord's answer as the accepted one, since he figured out correctly what was going on.


Creating a knock-off x86 compliant CPU isn't the same as a fake memory card. Worst case someone tried to pass off an older model but Intel changes the socket design every couple generations. Not to mention these CPUs also contain a GPU.

  • Yes it's possible to update the microcode - Intel offers paid upgrades for some of their CPUs.
  • CPU 0 simply refers to "the first CPU" if you have a multi-CPU or multi-core system.
  • Doubtful it's a sample.
  • Run a benchmark and compare the output with online results for that CPU model
  • Intel AMT requires a compliant BIOS
  • Interestingly his processor claims to be a newer model of a later generation than what he bought, tho both are cross compatible. This is just plain wierd. He bought a SB core i5, and his system thinks its a IB core i7
    – Journeyman Geek
    Aug 23, 2013 at 3:04
  • That's true, it should be a CPUID 0206A7h Aug 23, 2013 at 3:06
  • @justbrowsing CPU 0 does actually NOT mean "first CPU" (see my answer) and it was a sample after all. But the rest of your answer is useful. Thanks.
    – Markus A.
    Aug 29, 2013 at 4:03
  • My answer was written BEFORE the output from CPU-Z was posted. In certain CPU stat utilities (mostly Linux-based) CPU 0 refers to either the first CPU or first core. See /proc/cpuinfo for example. Aug 29, 2013 at 5:10

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