If I would upgrade right now, I'd go for Intel motherboard and Intel CPU. My experience with AMD was crappy: back in K6 days, their CPUs were getting messed up really quick (two of my CPUs died).

I've got my first Athlon and it got burned out even before I took the PC out of the store. They replaced it 5 times (including the fans - the last one looked like an air conditioner!), all 5 CPUs got burned out and they even got angry at me, just because I wanted them to show me that PC was working properly. Then I went to Intel line. Never had troubles with it.

After recent lightning strike, my motherboard (along with my flat screen and DSL modem) was burned out, I bought another Intel board and it works like charm. Guess what? When I was buying motherboard, I guy came in with his latest AMD 64-bit CPU being burned out.

From all this, all I can say is that AMD makes low quality processors. Seriously, no matter if they go to 128-bit arquitecture now or super-bandwidth-transfer-feature, but what would you prefer, a 32-bit CPU that will work for many years or state-of-the-art MEGA-bit CPU "from the future" which gets burned out in seconds? I prefer the first.

Just my few cents...