Hey as far as costs go yours ARE NOW FREE
You paid for em,
anything new costs MORE

ok from wiki,


Name Cores Threads Frequency Turbo Boost Multiplier* L2 cache L3 cache TDP Release Date[6] Price (US)[7]
Core i7 Extreme 3980X[8] 6 12 3.40-3.50Ghz 4.00-4.10Ghz Fully Unlocked ? ? ? Q4 2011 $????
Core i7 Extreme 3960X 6 12 3.30GHz 3.90GHz Fully Unlocked 6 x 256KB 15MB 130W November 2011 $999
Core i7 3930K 6 12 3.20GHz 3.80GHz Fully Unlocked 6 x 256KB 12MB 130W November 2011 $583
Core i7 3820 4 8 3.60GHz 3.90GHz Limited Unlock 4 x 256KB 10MB 130W November 2011 $294

[edit] Server ProcessorsInformation for the server LGA 2011 socket processors can be found in the table below.

All models support: MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, Enhanced Intel SpeedStep Technology (EIST), Intel 64, XD bit (an NX bit implementation), TXT, Intel VT-x, Intel VT-d, Turbo Boost, AES-NI, Smart Cache, Hyper-threading.
Name Cores Threads Frequency Turbo Boost Multiplier L2 cache L3 cache TDP Release Date Price (US)[9]
Xeon E5 1660 6 12 3.30GHz 3.90GHz ? 6 x 256KB 15MB 130W Q4 2011 $1080
Xeon E5 1650 6 12 3.20GHz 3.80GHz ? 6 x 256KB 12MB 130W Q4 2011 $583
Xeon E5 1620 4 8 3.60GHz 3.90GHz ? 4 x 256KB 10MB 130W Q4 2011 $294

Hmmmm, if the xeon e5 1650 is really gonna be 583, might be time
for a dual box...

I like the core i7 3930K 6/12 3.20GHz 3.80GHz Fully Unlocked 6 x 256KB 12MB 130W November 2011 $583 ~£375.
Still a bit too pricey for me, but for 6cores/12threads, rather than the 4/8 of the i7-2600K @ ~£220, the 3930K is relatively only £45 over the odds, and that's without considering the clock for clock performances; so as the 3930K would be more productive clock for clock, the price is roughly par for par; you get what you pay for. This makes things good for upgrading; just get what you can afford and don't worry about performance - it will be fairly linearly related to price (with the obvious exceptions of the very top CPU's that you have to pay well over the odds for), assuming you get an HT K model.

Reviews generally put the 3930K at slightly faster than the 990X but not much overall. That said the maths tests Whetstone/Dhrystone were better. Until someone posts average points per day running a specific project it will be hard to know for sure.

An i7-2600 has a TDP of 95W, but only has 4 cores (8 threads).
If you divide 95W by 4 and multiply by 6 that would be 142W. That means in terms of energy efficiency a 6 core SB (130W) would be more efficient than the present 4 core variants! Hardly an obstacle.

I think those already with 6core processors should wait until 8core processors turn up.

Three 2600-K based computers would use more power than two i7-3930K based computers:
With the exception of the CPU's the systems would use about the same power; the new motherboards still support 1.5V memory modules, but just up to quad channel. So going by my 165W that would be 495W for three i7-2600K systems and 400W for two i7-3930K computers. That's assuming the full 95W and 130W respectively is actually being used when crunching (would require OC'ing); the i7-2600K CPU uses around 65W crunching at stock (measured on two systems).