I believe I can help you with this issue considering i had the same problem with my GF2 MX400 TV on a FIC AN11 Stealth Via KT266a MB.

if you havnt flashed your bios (not shur if that issue has even been addressed in a flash)

the solution is :

First check your IRQs if there is 3 devices on the IRC containing your Video card .*mostly likely it will be* Video card, AC97 enhanced audio control and modem .... then your issue lies right there..

However the Bios funtion for assigning IRQs doesnt exactly work right.. the solution is going to be an odd one but just trust me

Go into bios and turn off USB mouse support.. if you have a USB mouse dont sweet it as most of them run off a Proxy program in windows...(has not problems out of his USB mouse) accept the 4th and 5th button not funtioning like programed (4th acts like the wheel as well in a way)

by doing that your AC97 EAC will move down one IRQ .. your 3D games will start funtioning properly .. but as far as the boot problem.. i didnt notice that but maybe i missed it.. Good luck, hope this helps