P5Q BSOD on Boot when installing Sound Driver on Win 7 X64

Hi, I'm at my wits end here. Re-installed Win 7 X64 about 20 times now! I'm getting various BSOD's after installing a fresh Win 7 X64 after trying to install sound drivers (and SATA drivers - see below) on a P5Q motherboard.

I've tried different versions of the drivers (Realtek HD Audio) from R271-R285 with no difference at all. Also tried the default Asus ALC drivers.

If I install an Nvidia graphics card driver (with HD Audio driver) same thing too, If I disable the onboard HD Audio and re-boot, I still get the crash!

The weird thing is, that I have been happily using Win 7 X64 for about 2 years prior to this with no problems at all! I just wanted to have a nice clean fresh OS.

The only thing I can think of that could be the cause, is possiby the motherboard is faulty, as at one time the onboard NIC packed up, and disabling it / re-enabling it in the BIOS made no difference. Then suddenly it started working again.

I was also triple booting XP Pro / Win 7 X64 / Win 8.1 X64. The sound drivers on the other 2 OS's work fine, no crashes or anything! I hear no sound problems or any other anomalies when using Win 8.1.

I've subsequently got rid of XP and now just dual boot Win 7 / Win 8.1.

The drive I'm installing Windows 7 X64 on is a Kingston V+220 (SVP200S). It is completely clean, formatted, zeroed, aligned and checked with AS-SSD, which reports its health at 99% and 8 years life left.

I also tried integrating all Windows 7 updates (all 180 of them to Jan 20th 2015) into the Windows 7 ISO (installed by USB btw), it makes no difference.

I know about the ATK0110 file. Installing the 2009 version makes no difference to the blue screens on boot.

I've tried installing sound drivers before AND after using the v9 and v10 Intel chipset .inf installer, with no difference.

I've tried installing in AHCI mode and Enhanced IDE mode. No difference other than BSOD messages. With Enhanced IDE mode I was getting a IRQ less than or Equal 0x0A error. In AHCI mode I'm getting STOP 0x7E error.

To re-iterate. The install goes absolutely fine. I set a system restore point, then install a sound driver and boom - crashes on boot. Do a system restore and all's fine again.

Surely if the motherboard was THAT faulty, Windows 8.1 would crash too?

Can anyone PLEASE help me sort this out as it's driving me crazy and I just don't know what to do next.

I've just found that I get a STOP 0x7E error after installing the default SATA drivers (IMSM_V8901023) too.

I also tried doing a fresh install on another hard drive (there are 4 altogether including the SSD). It made no difference at all. As soon as the sound drivers were installed - BSOD on boot.

Nothing is fixed! Windows 7 X64 crashes on reboot after installing SATA or sound drivers.

Was leaving changing the graphics card as a last resort. I have a relatively new card installed (GTX 750 Ti). Luckily I kept my old GTS-250.