Matching CPUs for 2012 MP upgrade?

[Thom2]

My old 2012 Mac Pro has dual 6-Core Intel Xeon Processors.
I want to upgrade to Dual-X5690s, but I keep hearing the processors need to be a matching pair.
- Does this mean I can't buy a "X5690" from one seller and another "X5690" from a different seller?
- The more I Google about what "Matching Pairs of CPUs" the more confused I get.
There's something about "stepping", which I have No idea how that relates to a CPU.
-- I get many conflicting answers, and all I want to do is upgrade my Old Mac Pro.

.....Thanks Thom

 

[chinesestunna]

Thom welcome to the forums. Typically when talking about "Matching Processors", it's the "stepping" (S-Spec number) or basically minor revision of a certain model, in your case, the X5690. Some CPU models will go through these revisions during their production run and will have a different stepping to differentiate, what makes them not work in a pair is typically due to feature differences (if any) between these revisions. With that said, it's safe to get "matched pairs" but I've seen folks with mismatched and even different models working together however I don't recommend this.

Back to your chips in question, great resource is CPU-Upgrade.com's page on it, you can see this chip only has a single revision:
S-Spec SLBVX (B1 Stepping)

stole this image online, see the red arrow - you can see the S-Spec number on the cover.

TLR - as long as stepping/S-Spec numbers match you're fine, in the case of X5690 pretty much any official version will be fine.

Bonus: X5690 is about $95-100 each on eBay, while X5680 is about 5% slower and only about $50, even found a nice seller selling X5680 matched on ebay selling "matched pairs" for Mac upgrades