Doug,

I'll chime in here with the sad news that a 4 year old computer is actually OLD and you need to get ready to say goodbye.

Unless you're running really advanced video editing stuff, you actually don't need a lot of processor power. RAM is the magic, and if you want a lot of RAM you need a modern OS that can talk to all of it well - like Windows 7 or - dare I say it - Mac OS X..

But the real issue here sounds mostly like a hardware durability issue, and in that area, we're quite happy with HP hardware these days. I run a system at work that's used for high-end data visualization and we've got some kind of fancy Nvidia card, 2 drive RAID and 4GB of ram in there and it's on 24/7 crunching numbers and no problems at all.

We also - like others have suggested - build our own systems from time to time. Decent motherboards, RAM and especially a solid cooling system is all a good idea.

But have a look at the HP stuff, you might find a system you'll be happy with.