q9550 C1 or E0 Stepping

Looking at one of these for a new build; but am torn inre steppings.

Found this short summation: http://tcmagazine.com/comments.php?shownews=21241&catid=2

Checking out the various forums (so far) has not led to anything conclusive. I can guarantee myself an E-0 for $13.00 bucks more at one etailer... but it's not really a question of the price difference, I just want to be done with this build, and move on.

Any help/suggestions would be appreciated.

Thanks.

you are going to want an e0 stepping, usually a better overclocker and temps might be a little cooler.

newegg is shipping E0's now.

They might OC higher, and might get a lower VID but i wouldn't pay anything extra for one.

Further searching results in:

The major fixes from C1 to E0 stepping for that chip are:

AV37. Performance Monitoring Event IA32_FIXED_CTR2 May Not Function Properly when Max Ratio is a Non-Integer Core-to-Bus Ratio
AV41. VM Exit with Exit Reason “TPR Below Threshold” Can Cause the Blocking by MOV/POP SS and Blocking by STI Bits to be Cleared in the Guest Interruptibility-State Field
AV44. NMIs May Not Be Blocked by a VM-Entry Failure
AV45. Partial Streaming Load Instruction Sequence May Cause the Processor to Hang
AV46. Self/Cross Modifying Code May Not be Detected or May Cause a Machine Check Exception
AV47. Data TLB Eviction Condition in the Middle of a Cacheline Split Load Operation May Cause the Processor to Hang
AV49. RSM Instruction Execution under Certain Conditions May Cause Processor Hang or Unexpected Instruction Execution Results

None of which is truly major, and may be addressed in BIOS. Short of reading the Intel PDF- and from which I gather there are no real refinements, just microcode fixes.

Antares Digital has the Q9550 for $262.00 plus $7.00 s/h; with the option for an E0 for $13.00 more, which would bring it to more than the Egg's current price. Anyhow, so much for MSRP. Let's see what Microcenter does in the next week or so, when they price-match their CPU's to the Net.

Best to all...

What are your intents? If you intend to OC then youll want an E0. If your not going for a crazy OC or anything then a C1 will be fine.

E0 > C1

The performance is identical. The only differences to the end user are possibly small voltage and heat/power usage drops, and greater overclocking potential.