Motherboard: Asrock N68C-S UCC

Motherboard BIOS version: American Megatrends Inc. P1.60, 2011-09-19

Processor: x86 Family 15 Model 107 Stepping 1 AuthenticAMD ~2

RAM: 3 072

Windows XP Professional

As i said in title, after i install VGA my comp becomes slow and laggy, much worse then it was on my previous motherboard(gigabyte ga-ma69gm-s2h), and i'm pretty sure that it's this driver fault(after i install and reboot i notice that 'change')

Any ideas how to solve it?