關於checksum error及鎖頻的問題可以看這邊

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其中大意如下:
在比對9700p及9700.9500p之後發現在bios中的00000070h
該位址中的44 76 4e 37 91為問題的所在
將91改為90之後即可以將bios超頻
而修改方法可以使用ultraedit或是wincv

Address Line: 00000070h
Originally: 44 76 4E 37 91 08 02 10 02 00 00 00 00 00 00 00
Edited: 44 76 4E 37 90 08 02 10 02 00 00 00 00 00 00 00

而會顯示出checksum error的情況是因為9700p跟9700的Device ID不同
所以在編輯程式中會出現下列情況
但是不影響修改bios


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原文如下
Warp11's Bio's Update Info (cut and pasted from his site)

I did a comparison of the 9700Pro BIOS, the 9700 non-pro BIOS, and the 9500Pro BIOS and was able to find the one hexidecimal value that is keeping the 9500Pro and 9700 non-pro from overclocking.

Address Line: 00000070h
Originally: 44 76 4E 37 91 08 02 10 02 00 00 00 00 00 00 00
Edited: 44 76 4E 37 90 08 02 10 02 00 00 00 00 00 00 00

ATi is setting the same hex value on the 9500Pro and 9700 non-pro cards to keep them from overclocking. I tested this change on both a 9700 non-pro and 9500Pro and it works. All of the overclocking utilities functioned correctly...Rage3D Tweak worked great with the new BIOS!

You may need to uninstall/reinstall your ATi Drivers and Control Panel.

The reasoning behind these BIOS's:
The Radeon9700Pro, 9700non-pro, and 9500Pro all share the same R300 GPU.

The 9700Pro and 9700non-pro are virtually identical, albeit with different memory.

ATi chose to give the 9700Pro Device ID: 0x4E44
ATi chose to give the 9700non-pro Device ID : 0x4E45

The question I asked myself was why did ATi do this? Virtually identical hardware that share EXACTLY the same drivers!

The only logical conclusion was that they wanted to lock all of the cards with Device ID: 0x4E45

The 9700non-pro and 9500Pro both share Device ID: 0x4E45 even though they DO have a significant hardware difference (the memory bus width).

I chose to give all cards with the R300 GPU the same Device ID that the unlocked 9700Pro has...0x4E44.

There are no illl effects to doing this! The cards share the same driver set.

I think of it like this...if the 9700Pro=9700non-pro and the 9700non-pro=9500Pro (based on having the same Device ID), then the 9700Pro=9500Pro. This equivalence is based from a Device ID/driver standpoint!

Could ATi start locking Device ID: 0x4E44? Of course they could, but that would mean a FULL lockdown of every card that they currently produce. If they did this, it would be too blatantly obvious what they were up to. I don't think they would risk that kind of bad PR.

"Won't it be a matter of time before someone finds out the inf option that enables the clock locking in the first place?" Possibly, but it hasn't happened yet and everyone that makes an overclocking utility has certainly been trying. The problem with correcting this issue from the software side of it, is that ATi could easily change things around in each driver set that they release...ATi controls the software, but they can't change the BIOS on your hardware. Unless ATi goes into FULL lockdown mode, this BIOS fix will work.

I hope that everyone understands my reasoning behind what has been done to correct this BIOS issue.

I didn't need to make any significant changes to the 9500Pro BIOS to get it working. I actually did it while drinking my morning coffee