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.