Older ubuntu versions will have problems with the AMD 'A' series CPUs/APUs. Newer versions (11.10, 12.04) should work, you might get some bugs though.
Originally Posted by mathman48
are there any cheaper alternatives that have HD?
What do you mean by 'HD'?
If you mean 'AMD GPU intergrated onto the CPU, aka 'APU'' yes, there are cheaper versions. The A4-3400 is about as low as you can get with socketed CPUs, to get something cheaper would mean a E-350. Still a dual-core CPU, though slower than the A4-3400, and has a HD 6310 APU.