Depends. My main problem with "gaming" machines (i.e. non-xenon) is that you wont get ECC ram. FLicking RAM will wreak havoc to any financial results - a bad pixel does not change a game. I stick all ECC memory for my work machines.
Unless you're running advanced number-crunching software, you likely don't need either. Any i5 or i7 on a mobo with at least 2, PCIEx-16 slots should be plenty.
Or current single socket Xeon, of course. I've got single socket W3570s in mine and have yet to find a function which takes the CPU >10%.
There are two things missing from this thread - the purpose of the machine and your expectations Everybody is throwing out SWAG because you've provided no guidance - you haven't answered the 2 questions above... The one thing I do know - you're not a programmer/developer/Unix/Linux user. Those types wouldn't ask such a question unless you used to troll ET as j2ee.... Try answering these questions... Are you flush with cash and just want to buy the latest and greatest? Are you a "I build my own" or a "Love specs, but always fry my mboard - please build it for me" kind of guy? Do you need mobility? Are you going to .... watch screens all day? How many screens do you need? I'd focus more on getting the best network throughput (hint - wired) and video card(s). You'll only need above average CPU, RAM, and disk. run scripts or a low-end auto trading platform like Ninja? Real-time or EOD? secretly desire to run a data mining/compute environment? Run them on the same machine? If so, you'll want the best of everything you can afford.... That's a start. Figure out what you want/need, then seek the solution. The answers come pretty easily once you know what you want...