I have one Lenovo Think center M55 with Processor Intel E2140 duel core 1.6 ghz Socket 775 LGA
I want to change this one with Intel E 5200 duel core 2.5gz will it support?
NB: I already Have E5200 Processor
I Successfully changed the processor
More about :changing processor e2140 wtih e5200 thinkcenter m55
That cpu is a year older than the one thats coming out. So possibly not, if you install the processor it will either work or not work. If it didnt work it you would just get stuck at a bios error screen.
The intel core 2 duo E6700 is supported but I would go for the e6600, both are on ebay but the e6600 is much cheaper.
I would also consider trying to overclock your board if the bios allows you to on the chip you have or even the one you are getting.