There is no way to be certain without taking off the cooler and looking actual spec code. OEM numbers are always confusing.

I noticed the 2.8V comes in a Boxed version while the 5V does not. This would lead me to believe that anything that was pulled from a server is likely the 5V version.

Any update on this topic? Also looking to buy some 2.8V Xeons.

its a necro but why do you care about the xeon's voltage? ovbiously the core can't be using 5v/12v vcc, so the 5v/12v version must have its own integrated vrm to convert 5v/12v input to the core, just like the haswell.

The above partnumber belongs to a Proliant 8500 server and this uses for sure 2.8V XEONS as you can notice by the VRM boards in the manual. I also upgraded mine as it came with only 4 CPUs installed. Beware of the Compaq XEONS with green heatsinks, these are the 5/12V versions with internal VRM. If you find XEON CPUs intended for the use in an hp netserbver LH6000 or LT6000r, these are 2.8 V as well. I just can´t find any partnumbers for the hp parts.

noshutdown wrote:

its a necro but why do you care about the xeon's voltage? ovbiously the core can't be using 5v/12v vcc, so the 5v/12v version must have its own integrated vrm to convert 5v/12v input to the core, just like the haswell.

Don't blame some of us for not wanting to fry our hardware but just plugging away as parts for these systems is only getting harder for much of the world, I for one do not want to release the magic smoke on a careless mistake.