Its fixed now :)
I just installed Ubuntu on my PC. I lag a lot. My pc runs all other OS' at high speed, but ubuntu lags like hell. It worked on my old laptop.
XFX AMD Radeon HD 7870 Black Edition
AMD A8-3800 APU
2x4 GB 1333 MHz Ram
I installed the latest version of Ubuntu. 13.04 I believe.
I run Windows and other linux distros really fast, so why does Ubuntu lag?