CPUID brand string: T9500 (returns empty string)

CPUID brand string: T9500 (returns empty string)

Hello,

We use CPUID to extract the brand string of a processor.

Our CPUID code reports the processor name(brand string) for "Intel Core2 Duo CPU T9500 @ 2.60GHz" as a blank string.

(i.e. EAX,EBX,ECX,EDX registers do not contain any values)

The specification update doc for this processor (DOC 320121-002 August 2008) includes the following errata:

"AZ64. CPUID Instruction May Return Incorrect Brand String

Problem: When a CPUID instruction is executed with EAX = 8000_0002H, 8000_0003H, or8000_0004H, the returned EAX, EBX, ECX, and/or EDX values may be incorrect. Implication: When this erratum occurs, the processor may report an incorrect brand string.

Workaround: It is possible for the BIOS to contain a workaround for this erratum. Workaround doesNOT work for SLB5J and SLGAS processors.

Status: For the steppings affected, see the Summary Tables of Changes. "

However, this errata AZ64 states that it only affects Processor Stepping: E-0.

T9500 is listed in the specification doc as having Processor stepping: C-0.

Is the T9500 processor also affected by errata AZ64?

Does the errata AZ64 description "may report an incorrect brand string" also mean that it "may report empty values"?

Thank you for any feedback you can provide.

-glen

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For more complete information about compiler optimizations, see our Optimization Notice.

Before someone from Intel chimes in I can recommend you to check if you have latest BIOS update for your computer. I suppose that workaround is a microcode update -- it won't hurt to try whether that helps or your CPU is one of those S-Spec# affected.

Regards,
Igor Levicki

Hi Glen,

Did Igor's suggestion help? If not, we will send out another request to our engineering contacts to look at your post.

==

Lexi S.

IntelSoftware NetworkSupport

http://www.intel.com/software

Contact us

Quoting - Intel Software Network Support

Hi Glen,
Did Igor's suggestion help? If not, we will send out another request to our engineering contacts to look at your post.
==

Lexi S.

IntelSoftware NetworkSupport

http://www.intel.com/software

Contact us

Hello Lexi/Igor:

Thanks for the replies.

Unfortunately, upgrading the BIOS version did resolve the issue.

Below is the info I received from my customer:

BIOS Version
Before upgrade: 0137(AM8-0137-DI4)
After upgrade: 0140(AM8-0140-DI6)

Please let me know if there's any other info I could provide.

-glen

Hello Lexi/Igor,

Thank you for your input on this matter.

After finally getting more logs from our customers pc, it turns out that CPUID was returning a processor name.
The problem was in our legacy code which did not get updated to deal with the extended model value for this processor.

-glen

Quoting - ggabriel
Hello Lexi/Igor,

Thank you for your input on this matter.

After finally getting more logs from our customers pc, it turns out that CPUID was returning a processor name.
The problem was in our legacy code which did not get updated to deal with the extended model value for this processor.

-glen

Hey Guys,
Thanks for sharing the topic and possible answers too................. :)

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