Win 7 wont start with OC'ed 710 CPU

aya1

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Hey. Thanks for your time

I have a Phenom II 710 with ASUS M4A785TD-V EVO, and i recently upgraded to Win 7 pro 64bit from XP home. Then i upgraded my BIOS to most recent available (M4A785TD-V-EVO-0506) from ASUS.com. Now i have problem OverClocking my 710 CPU.

With XP and original BIOS i easily got it to 3.4 ghz with AMD Overdrive, but capt it at 2.8 most of the time. Also, i was able to unlock the 4th core through BIOS, though not always stable and Overdrive gave wrong temps of -200 C, so never left it on.

Now, with Win 7, Overdrive shuts off at about 2.77 and if i try to get it higher through BIOS the windows won't start. Same with 4th core, no boot...

IGP overclocks no problem to 720.

Also, cpuID showed my ram at 830 mhz in dual channel with XP, now its 800. And Overdrive gives a much lower benchmark score for all things set to AUTO.

Thank you for any help.

 
Some mobo manufacturers have implemented BIOS updates that disable core unlocking. It may not be possible after the update.
I would recommend downgrading the BIOS to the previous version. Also, there are quite a few mod BIOS's out there on the web. I won't recommend that option as you'd have no way to be certain if it would brick your machine, but it may be a solution if you're willing to chance it.

I have heard that overclocking is easier in 32 bit systems, but it shouldn't be that much difference. I have been able to hit 3.8Ghz with my X4 940 under Win7 64 ultimate. (RC) I doubt the OS is to blame.

I had many trials and tribulations with the ASUS BIOS on my crosshair I board. I tried about half a dozen BIOS versions before I found one that would work with my system. I found the ASUS forums for the crosshair to be extremely helpful during that time, I recommend you check that out first to see what other folks are saying about your model.

 

aya1

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Hello, thank. I tried downgrading BIOS with EZ flash 2, but it would just say that its an older one, and wouldnt proceed with flash. So how can i downgrade?

Thanks again.
 

aya1

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could my current bios be the 32 bit and not compatible with 64 bit? If so, how can i change it if EEPROM is incompatible ?
 

aya1

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never mind, the latest 506 i got was for win 7 64, but i cant downgrade to 211 for win 7 64.