Thinkpad 600 Memory 288mb maximum ?

I have a TP600-45U. I have the most recent BIOS upgrade (54ww).Windows 98. I know 32mb onboard. I have two 128mb modules and one 64mb module.

Problem: The first slot will recognize full memory of any of the 3 chips. The second slot will only recognize 50% of whatever chip is installed. So instead of 288mb, I get only 224mb because the second slot only sees 64mb of the 128mb.

I have tried all the chips in the 1st slot and they all are 100%.
Tried all chips in 2nd slot and only 50%. It doesnt' matter if the 1st slot is occupied or vacant when testing in the 2nd slot, results are the same.

Am I missing a software patch or upgrade or is this a bad number two slot? Or is it something else at issue?

Any replies/possible solutions appreciated!

Kotre

 

well, 288 is the max for my 600E. one of my slots died, so instead of replacing the motherboard I put a 256 in the good slot, maxing out the memory at 288 with the onboard 32. This works and the computer recognizes all of it.

 

Very clever of you! When your slot died, did it recognize any memory at all? Did you use 256mb SDRAM PC66? Do you know if there is a diagnostic to test the slots?

 

415mb !!!
Wow! I tried your method of 256mb in the first slot with some SDRAM PC100 from a defunct Compaq Armada M700. It recognized the 1st slot 100% so I thought why not try the 2nd slot?
It sees 50% of the next 256mb or 128mb! So I have 256,128, and 32 which reads out on my BIOS report as 415mb! I did have to go into msconfig (advanced) and reset the memory to 512mb, thats it!
Thanks alot for your input! Problem solved with a bonus!

Kotre

BTW, the new memory was Simpletech.

 

congratulations then.

actually, it was the IBM tech who suggested upgrading the memory for $50 instead of the motherboard for $600. Yeah, sometimes it would recognize the slot, sometimes not. the working one has worked perfectly since then (~4 years)