Mixing CPUs in Dual Board

[Rand__]

I remember somebody confirming that running two different CPUs in a dual board does work.
I can't find the thread to check caveats so thought I'd ask.
Potentially looking to run a 2680 and 2640 (v4 qs) in a dual system. Same clock speeds but different core count...

 

[nthu9280]

Not sure how relevant/vaild the below post for 2011-3 generation. If that is still true, your combination is not compatible. It refers to the data sheet of 5500 series. May be current Intel e5-26xx V4 datasheet sheds some light on the same topic.

See post #4.
Different processors on a dual socket motherboard?

 

[Patriot]

They will run at lowest common denominators, sometimes you get lucky and turbo will be higher than lower one's max. Stick the faster chip in the first socket.

Steppings do need to match, sometimes you can get away with minor revision different but main stepping differences will most likely cause instability or failure to post.

The last I have personally tested was v2, and they were still matching core counts.

 

[Rand__]

Mixing Processors

Intel supports and validates two configurations only in which all processors operate with the same Intel® QuickPath Interconnect frequency, core frequency, powersegment, and have the same internal cache sizes. Mixing components operating at different internal clock frequencies is not supported and will not be validated by Intel. Combining processors from different power segments is also not supported.

Note: All processors within a system must run at a common maximum non-Turbo ratio. The system BIOS may be required to program the FLEX_RATIO register if mixed frequency processors are populated.Not all operating systems can support dual processors with mixed frequencies. Mixing processors of different steppings but the same model (as per CPUID instruction) is supported, provided there is no more than one stepping delta between the processors,for example, S and S+1.S and S+1 is defined as mixing of two CPU steppings in the same platform where one CPU is S (stepping) = CPUID.(EAX=01h):EAX[3:0], and the other is S+1 = CPUID.(EAX=01h):EAX[3:0]+1. The stepping ID is found in EAX[3:0] after executing the CPUID instruction with Function 01h. Details regarding the CPUID instruction are provided in the Intel® 64 and IA-32 Architectures Software Developer's Manuals,Volume 2A: Instruction Set Reference, A-M





So I'd say no

Thanks for the pointers.

 

[BlueFox]

Sounds like a there are a few possibilities then. Here are some examples where QPI, cache, TDP, and clocks match:

2648Lv2 + 4634Lv2
2695v2 + 4657Lv2

 

[Patriot]

I might try a few combos tomorrow for kicks... but um... a 14c A1 and 22c A1 did not post. Most of previous mixed chip combos were all same core count, just different clocks.