Thinkpad T40 adding Dothan C0 stepping support

[wastedyears]

Hello all.
Few days ago I've decided upgrading Thinkpad T40 from 1.3ghz Banias to 1.7ghz Dothan, but unlucky bougt 735A with C0 stepping, which is not fully supported so frequency constantly stays at 598Mhz.
Mainboard model 237322G. Embedded microcodes is 3.04 and latest BIOS is 3.23 and can be downloaded here:
https://thinkpads.com/support/Thinkpad-D...uj37us.exe
Personally I tried to replace bios microcodes 694 with 6D8, to which C0 stepping dothans belong imho, but no success - got error during flashing bios "can't merge cpu hash data. make sure *.hsh file is correct".
I'm in stumble. What to check next? Any ideas?

[DeathBringer]

Post a screenshot of Mainboard tab of CPU-Z.
Go to BIOS and do Load Defaults, save and reboot.
Make a screenshot of ThrottleStop (main window) with running TS Bench.
And make a screenshot of regedit with expanded key HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0

[wastedyears]

Thanks for fast reply.
Done.
Throttlestop 2.99 shows error Unsupported CPU

[DeathBringer]

OK.
Make DOS USB-stick (e.g, by Rufus), download and unzip all files for the modded version of CHECKUP7 to this DOS USB-stick.
Boot from this DOS USB-stick and make a photo of the screen with results.

[wastedyears]

Yes, got it

[DeathBringer]

Try to flash my mod.

[wastedyears]

I've tried, but unfortunately, there 's error at the very end

[DeathBringer]

there 's error at the very end

Show it.

[wastedyears]

there 's error at the very end

Show it.

[DeathBringer]

Install supported CPU and try again.