Which will give me better performance on Win 7 x64

[jandatec]

One Dual Core 2.8 Xeon CPU 2x2mb Cache or
Two Single Core 3.4 Xeon CPUs 2mb Cache

 

[Lmeow]

Which Xeons exactly? Two single core 3.4GHz Xeons with 2MB cache each would probably be faster, but it really depends which CPUs.