I have been running AMD Overdrive under Windows XP SP3 without any problems. I just installed Windows 7, and the latest version of AMD Overdrive.  It loads OK and all panels work when the program loads.

In the simple interface for overclocking, if I set the lowest value (or any value above zero) and APPLY, Windows 7 freezes.

My Computer:

Motherboard: Gigabyte GA-MA790FXT-UD5P

CPU: AMD Phenom II 720

Graphics Card: HIS 4870HD

Memory: 4GB DDR3 1066

All drivers are up to date as of this week

Make sure your Power Options (Control Panel->System and Security->Power Options) is set to "High Performance" instead of "Balanced (Recommended)", which seems to be the default.

"Balanced" lowers the CPU voltage at idle, so many of your AOD performance settings will self-destruct.

My Setup: 
Biostar TA790GX XE
Phenom II 720 @ 3.4 GHz (stock voltage) or 3.2 GHz w/Auto ACC ;) (stock voltage)
4GB Corsair XMS2 DDR2-1066 (5-5-5-15, 2x2GB)
Windows 7 Professional (64-bit)  XP Mode is so cool
Sapphire HD4670 512MB (GPU 800MHz/Mem 938 MHz) 
24" Samsung 2443BWX (1920x1200 max resolution)

I left Intel in '08 because their socket path sucks. 

Thanks for the reply. Unfortunately, I already have the Power Options set to 'High Performance'.  My feeling is that the problem is with AMD Overdrive on Windows 7.

I have Win 7 64 bit Ultimate, and just tested overclocking with AMD Overdrive.  Have not experienced any crashes.

Asus Crosshair III, Phenom 955 BE, 8 gigs Corsair Dominator 1600 mhz, VelociRaptor X 2 RAID 0, BFG 295 GTX, CoolIT System, Medusa 5.1 headset, EnerMax Galaxy 850 watt psu

Same thing happens to me (Win7 64 - AOD 3.1) if I have ACC enabled. If you're not using it to unlock extra cores try disabling it. Or else just do your overclocking from the BIOS.

Thanks. I did turn on ACC to see if I could unlock the fourth core (it didn't), and never turned it off.

I'll turn it off, and give it a try.

Currently I am running a Gigabyte application that came with the motherboard which effectively does the same thing as AMD Overdrive.

Windows 7 issue, youre not the only one fella,

Just google it or look on here, loads of people same issue.

I have a call logged with Microsoft as they have also told me they are looking for fix

It happens to me when watching media or playing a game, anything really that stresses the card a bit