I was looking to extend the life of my gaming rig (see sig) and thought I'd entertain the idea of a Xeon CPU upgrade. Price, TDP, base multiplier for OC, etc. has led me to the X5675. So two questions:
 
1) This seems like a good bang-for-the buck Xeon option for the X58 SLI, agree?
 
2) I see them listed with "SLBYL" as a prefix and sometimes with a "Z5" suffix. Can someone help me ID what those mean, how they may or may not work with my plans, and what benefits/drawbacks there are to other versions of the X5675?
 
Thanks!

 
I think you happen to have the x58 model of motherboard that supports Xeon, unlike the rest of us with soldering irons and a broken turbo boost.  I wouldn't focus on prefixes, signs, or portents.  It doesn't matter.  Focus on getting an X5690.  That's it.
 
http://www.ebay.com/itm/Intel-Xeon-Hc-X5690-Processor-/262092897545?hash=item3d05f43d09:g:HsIAAOSwQTVWCW1e
 
No need to half ass it now.  Prices have jumped off the ledge and hit pavement.
 
This processor is equivalent to the Intel® Core™ i7-990X Processor Extreme Edition (12M Cache, 3.46 GHz, 6.40 GT/s Intel® QPI) at 1/3 the price. 
If you can use a Xeon proc, take full advantage of it.  It's a $1500 processor for $200.

Thanks. I don't remember all I was reading. But the basic gist was that the 5675 has the best clock and runs at a lower TDP. The implications are that overclocking should come out similarly as the 5690 at 60% of the price. That's why I was asking what I was asking.  Maybe I'm being cheap, but the 5675 may run cooler and OC at least as well. Or am I missing something?

It does have a lower TDP, that's true.  But not by much.
 
http://cpuboss.com/cpus/Intel-Xeon-X5690-vs-Intel-Xeon-X5675
 
I didn't know you were overclocking, but if you are overclocking with 12GB triple channel ram you aren't going to get very far.  Keep that in mind as well.  It's your call, but it comes down to how much you want to spend or not spend.  If that's the bottom line, and you are looking for D0 yields in the Xeon space, it isn't going to matter.  They are all spec'd the same as enterprise chips.

Those are things itching the back of my brain, true. I'm going to keep doing some homework on it before I decide. Thanks!

Broke down and called EVGA's tech support. My motherboard would require the Westmere mod. EVGA would do it under the board's lifetime warranty which is very, very nice. But I don't think I'm going to send it in and wait a couple/few weeks just now.  Perhaps in the future. Thanks again!

I vote for doing it. I've done the westmere mod on my E762 and it works perfectly with a X5650 & X5670.
Just FYI, the only difference between the X5650-X5690 is the multiplier, TDP and all that stuff doesn't matter at all, so get the X5650 instead since it's the cheapest.
 
As for oc'ing with 12GB+ of ram, it depends on what IC's your ram has, your motherboard and what the IMC can do, I've run my 24GB's (6x4GB) @ 2100MHz 9-10-10-27 1T 1.6v without problems. Albeit the ram I have is known to do 2600MHz+.
 
Also, the X5690 is not equivalent to the 990X they have completely different architectures. On the other hand the W3690 is the direct Xeon equivalent of the 990X except it has an ECC memory controller, it also shares the unlocked multiplier (on most motherboards).  
 

It's worth the mod really as my board was Rev 1.2 and didn't need the mod and the X5660 was a drop in support and an idea of what x58 still has to offer..
 
http://www.3dmark.com/fs/5829224
 
 

Sweet! Yea and OC'd 5660 can match up against a 3930k 
THis guy did a pretty good review about it....excellent info..
 
http://www.overclock-and-...eviews/28-x5660-review

tucker147
I vote for doing it. I've done the westmere mod on my E762 and it works perfectly with a X5650 & X5670.
Just FYI, the only difference between the X5650-X5690 is the multiplier, TDP and all that stuff doesn't matter at all, so get the X5650 instead since it's the cheapest.
 
As for oc'ing with 12GB+ of ram, it depends on what IC's your ram has, your motherboard and what the IMC can do, I've run my 24GB's (6x4GB) @ 2100MHz 9-10-10-27 1T 1.6v without problems. Albeit the ram I have is known to do 2600MHz+.
 
Also, the X5690 is not equivalent to the 990X they have completely different architectures. On the other hand the W3690 is the direct Xeon equivalent of the 990X except it has an ECC memory controller, it also shares the unlocked multiplier (on most motherboards).  
 

erm... the 990x 'Gulftown' and the X5690 'Westmere' are based on the same 32 nm Westmere-EP silicon architecture. Both are essentially a 32nm shrink of the Nehalem.