Okay so I'm currently running Dual E5-2670's but they put out a little bit too much heat and I'm looking to swap for some different CPU's. I ordered a pair of E5-2650L's, but I'm not sure they will be powerful enough for me. I've seen these E5-2651 v2 chips on eBay and they seem really interesting. They are 12 core low clock chips, but since they were not retail CPU's and only sold to OEM's there isn't much info available on them. They aren't on Intel's website and I can't find a TDP listed for them anywhere. If anyone has any info about this CPU other than clockspeed and cache I'd love to know. I don't want to buy them unless they are much lower TDP than my 2670's.

Keep in mind for any given chip architecture (generation) the total power per unit of work done will be very similar. The power limited version just throttles back to keep from emitting too much heat over a given period of time. So, if you have an identical task for the two CPU's to complete, the non L version will be done sooner, with a spike of heat, vs. the lower but longer heat output of the L processor.

 

In the case of a NAS, much of the heat (and work) comes from the drives spinning, so getting the CPU work done sooner and allowing the drives to spin down may actually lower overall power and heat.

 

TLDR; Power consumption is a complex subject, substituting a low power CPU may not have the desired overall effect.

9 minutes ago, jonathanm said:

Keep in mind for any given chip architecture (generation) the total power per unit of work done will be very similar. The power limited version just throttles back to keep from emitting too much heat over a given period of time. So, if you have an identical task for the two CPU's to complete, the non L version will be done sooner, with a spike of heat, vs. the lower but longer heat output of the L processor.

 

In the case of a NAS, much of the heat (and work) comes from the drives spinning, so getting the CPU work done sooner and allowing the drives to spin down may actually lower overall power and heat.

 

TLDR; Power consumption is a complex subject, substituting a low power CPU may not have the desired overall effect.

Thanks for the info. While that is normally true, I know there are variances in manufacturing that make certain chips more or less efficient than the norm. That is why Intel can sell certain CPUs for such a high amount (since they were binned as the "more perfect" chip). 

 

For my server the drives stay spun up all the time, as they are constantly being used. Right now I am encoding most of the time with my Dual 2670's. I would like to upgrade to the V2's, but I'm just not sure which ones to get.