I have been using the machine I built for a good week or so and it runs well enough that I am not going to worry about the HP for now. Mint 14 x64 Cinnamon runs nice and fast on this hardware. I used an Antec gaming case with lots of fans, a Thermaltake 650 watt power supply, a Biostar AM2+ mainboard with thermal protection, 4 GB of Corseair RAM with a lifetime warranty, and the duel core processor is running at 2.9 GHz. I used a huge heatsink with heat pipes and arctic silver. The only reason this machine just sat around is because sometimes it would not boot right, it would stop on verifying DMI pool data. I fixed the problem by installing a new combo drive. The original drive appeared to work fine but it came out of a lightning struck computer that I salvaged parts from. Something in the firmware must have been messed up I guess.
I have the worst luck with computers.... Maybe my luck is changing though.
I took the 2 TB hard drive out of the HP and installed it in the home built system, it's a Western digital Green drive and I put it right in front of one of the front case fans and it is staying nice and cool. The only component that really sucks is the GT 220 graphics card, it works alright but it's nothing special. I have a high end ATI graphics card that was given to me but it has always been a pain because the drivers are never worth a darn.
I felt really bad when the HP quit, I really liked how well it ran Linux. I guess I will just get another board and chip for the home built machine when it no longer does the job.
On a good note, I finally got Mint 14 running nice on my HP laptop! The laptop has a quad core processor and 8 GB of RAM but I was constantly having issues with the hybrid graphics with Mint. Just for the heck of it I installed Mint 14 x64 Cinnamon again and installed all the updates. After all of the updates were installed the graphics are working right with the open source drivers! At first the graphics were horrible, lots of artifacts and black around anything I would open. The problem with 6 images of the greeter and booting to a black screen appear to be gone too. I have rebooted the laptop like a million times with no problems anymore.
I was real happy to get both these machines running Mint 14 and best of all, I do not have to spend any money to fix anything. I will just recycle the remaining good parts from the HP desktop when I find a use for them.