Hi, I've bought a new PC with the following configuration:
- ASUS P8H77-V Motherboard
- i5 processor
- AMD Radeon HD6450 with dual monitor (DVI+VGA)
...
- Microsoft keyboard and mouse (Wireless desktop 800)

I've been trying for several days now to get everything setup correctly:
- On install (12.04 64-bit), network is not recognized (fixed by installing linux backports modules)
- Nor Unity neither Gnome shell recognizes dual monitor after installing fglrx (had to move to XFCE)

Now, everything seems to be working fine except for the mouse and keyboard, with randomly (or apparently random) have lag. Mouse stops moving smoothly and keyboard stops responding (and after a while enters some of the keys I've pressed all together). It's not that they freeze, but become extremely laggish.

I've been looking for a solution but I couldn't find one. MB's box says that it supports linux with latest kernel versions. However, when I tried to install kernel 3.4+, the graphic card would stop working, as fglrx drivers don't support newest kernels.

Any ideas?
Thanks!