Definitely the comp posted first in my specs. Gigabyte probably has the best, most stable, unlocking feature for PII CPUs. Thanks to that, I am currently running my PII 550 BE as a quad B50 and overclocked to 3.6 GHz at only 1.4 vcore. Also, that system makes use of a 4850 X2 I bought from Shadowfold, so it is definitely the more powerful system right now.
The other system with the M4A78-E isn't much less powerful though since it is sporting the 940 BE and two 4830's in Crossfire. This was mostly a spare part system that I whipped up a few months ago. Nobody was buying the parts locally, so I just decided to make it a build. Up until now it was being used in my living room for general entertainment.
Thanks to your GTX 260, the new micro atx htpc should come close in power but in a smaller package which will be nice since a full tower is kind of an eyesore in my living room. :P
Nope. I've never been into FPS games. Probably because I suck so badly at them. I've been an RPG geek all my life. Last year, one of my buddies decided to bring CoD4 over and spend most of his time killing me. He would stand right in front of me and I still couldn't hit him! xD