If you can find an exact Windows version that the PC shipped with you can do a clean install using the activation key on the COA sticker attached to the PC though it may require a robo-call to MS to sort the OEM batch-key.
How to Activate Windows 7 by Phone
If you can't find an exact same version, you could use the info in this tutorial to create an "all versions" installer of any version Windows installer, to install using the same method I posted above.
Windows 7 Universal Installation Disc - Create
Interesting idea. I think I'll look into that option.
Google is your friend.
My Computer
At a glance
W 7 64-bit UltimateIntel Q9550 Yorkfield8GB Dominator 8500C5DATI : XFX 5870
- Computer Manufacturer/Model Number
- * BFK Customs *
- OS
- W 7 64-bit Ultimate
- CPU
- Intel Q9550 Yorkfield
- Motherboard
- ASUS P5Q Pro
- Memory
- 8GB Dominator 8500C5D
- Graphics Card(s)
- ATI : XFX 5870
- Sound Card
- Realtek HD Audio 7-1
- Monitor(s) Displays
- 1x 47" LCD HDMI & 3x 26" LCD HDMI
- Screen Resolution
- 1920x1080P & 1920x1200
- Hard Drives
- 1x 80GB Intel X25-M G2 SSD : 1x 500GB & 1x 640GB WD Caviar Black(s)
- PSU
- Corsair 620HX
- Case
- Cooler Master RC-690
- Cooling
- Tuniq Tower 120, 2x 140mm and 3x 120mm case fans
- Keyboard
- Microsoft 500
- Mouse
- Razer Diamondback 3G
- Internet Speed
- 14 Mb/s
- Other Info
- 1x Koutech 3Gb/s SATA HDD Hot Swap Rack
