Just got a new rig together :
AMD A8 5500 APU 65 watt TDP
Asus F2 A55-M motherboard
8 gigs GSkill RipJaws 1866Mhz RAM
Thermaltake K8 Silent Boost Cooler I had new in the box.
Case, PSU, Hard drive, and DVD burner I already had.
I left Ubuntu on the hard drive, and did a reinstall. It saved all my home folders and data. Reinstall menu is found under Install option. Ubuntu will scan hard drive, find previous install, and give you options for the reinstall.
I picked an Asus board over others because Phoronics.com said that they were the most Linux friendly manufacturer. They were right. No install problems, no driver issues, Ubuntu repositories had all I needed, and downloaded the rest.
So if you're tired of your old hardware, take the leap, the water's fine.
I did get a bum stick of RAM, but system is stable running on 4 gigs in single channel mode. Newegg is in the process of replacing the memory. I send it out Monday. I want to play with my new toy till then.