Unable to boot Win7 after installing OnBoard Gfx driver  

Hello.

Here's a problem I got with the Onboard intel graphics driver.

After installing it, w7 won't boot. It loads the windows logo but freezes and won't load the os.
The only way to make it work is restoring, and obviously getting the said graphic driver deleted.

I've tried changing some UEFI (bios) settings, but nothings worked. Also btw, the system only works with the hard disk set on ide and it doesn't work using AHCI (the one that comes by default)

I've also tried installing Win8, but things went even worse, as I didn't even get the chance to boot w8 after installing the SO.
So that I had to come back to Win7 but unfortunately just with the standard vga driver-

I ran out of ideas, I have no clue what's preventing me from booting after installing the Intel graphics driver.

Could be that the driver got some kind of bug that the company would need to fix and update ?

The motherboard is an Asrock H61M-DG3USB3

HD Seagate Barracuda 1TB SATA3, although the mb has got only sata2.

the processor is an Intel G2020 ivy.

Any help would be appreciated :) Thanks

If Windows was installed in IDE Mode you have to do a registry edit to switch to AHCI after the fact.
AHCI : Enable in Windows 7 / Vista
If you press F8 at the correct time during boot up you should get the safe mode etc boot menu. Amongst those options is a Enable low resolution video (640x480), try that and if it doesn't work try safe mode.
Safe Mode