Thinkpad 600 freezes in Bootscreen

[hollydirk]

I have replaced the Pentium II 300 MHz cpu in my thinkpad 600 by a 400 MHz model.

Now booting freezes after memory size is displayed in the bootscreen.
Removing RAM and drives makes no difference.
Holding F1 while turning power on makes no difference - I don't get to the bios-setup.
When I remove the cmos battery the expected error codes are shown and I can adjust date and time - just as expected. But restart leads me to the frozen bootscreen again.

When I reinstall the old cpu everything is fine.

[BillD]

I have replaced the Pentium II 300 MHz cpu in my thinkpad 600 by a 400 MHz model.

Now booting freezes after memory size is displayed in the bootscreen.
Removing RAM and drives makes no difference.
Holding F1 while turning power on makes no difference - I don't get to the bios-setup.
When I remove the cmos battery the expected error codes are shown and I can adjust date and time - just as expected. But restart leads me to the frozen bootscreen again.

When I reinstall the old cpu everything is fine.

Bad 400mhz cpu or is the 400 a Celeron by any chance?

[hollydirk]

Are there any mmc-1 celerons? How coul I recognize one?

[ms5133]

Your processor should have this Intel nbr: PMF40002001AA


see here for more info: http://www.cpu-world.com/info/id/Intel- ... ation.html

http://www.cpu-world.com/CPUs/Pentium-I ... 001AA.html

[BillD]

Are there any mmc-1 celerons? How coul I recognize one?

Yes there are...

Here's one for sale on UK's Ebay... And they do NOT work in the 600's..

http://cgi.ebay.co.uk/INTEL-CELERON-400 ... 6883989913

[hollydirk]

I have checked, and it is indeed a Celeron 400 mmc-1 module.

Btw. does anybody know why it does not work in Thinkpad 600?

[BillD]

I'm not sure exactly why they don't work, I just know they don't..

Maybe they were made for another company's laptop..HP, Dell, whatever...I'm not sure...