Help me choose a Xeon CPU

[Cipher]

I picked up a Dell Precision T7500 that will be used as a temporary server until I finalize what server system I'm buying/building. At that time, the T7500 will become my main workstation machine.

It came with a single XEON E5640 (4 cores, 80w TDP), but I'm looking to upgrade it two low power Xeons. The ones I've been looking at are the L5639, L5640 and L5645 as these seem to offer the best combination of performance and low power. These are all 6 core and rated at 60w TDP.

Besides the differences in clock speed, are there any other differences between these three CPUs that I should be aware of?

Thank you

 

[Patrick]

Just wondering, why low power Xeons? What about the X5650? Heck I bet people on here have a few laying around.

 

[Cipher]

Hi Patrick,

I really didn't start thinking about these low power Xeons until I read the following article on the site - http://www.servethehome.com/intel-xeon-l5639-inexpensive-lowpower-6c-12t-xeons. I then started looking into which of the low power 6-core options provided reasonable performance while saving some power. Another reason is that these Xeons are pretty inexpensive on eBay. For example, the L5640's are going for around $65-70 each.

I like the performance of the 6-core X5650 you mentioned (higher frequency of 2.67 and bus speed of 6.4 GT/s), but they are rated at 95w which is 35w higher than the low power versions I was looking at.

Admittedly, I'm not sure what kind of cost difference this would be (2 x 60w vs 2 x 95w), but since I'm going to be running two CPUs I thought I'd be better off getting the lower power Xeons.

 

[Patrick]

Price should be about the same, no more than $5-10 more per processor. Here is a listing for 2 for $140: Lot of 2 MATCH PAIR SLBV3 INTEL XEON X5650 6 CORE 2.66GHz 12MB 6.40GT/s 95W PROC

The 35w TDP is max not idle. Westmere-EP was decent on idle power consumption. If you are using this as a workstation, I would get the X not the L. Low volume server, L not X.

 

[HellDiverUK]

Also check the Dell supports the L chips. I know when I upgraded the T5400 (the one I have is identical to my old work PC), the machine was VERY fussy about the chips used. At work we ended up having to buy a matching chip off Dell.