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.