Thinkpads Forum

Hi
I've bought a ThinkPad 600X few months ago .Initially it had 128MB PC100 ram and I wanted to add another 128Mb. I bought 128 Mb PC100 and put them in the other free slot. I started the machine and everything looked fine it detected 256Mb ram. After a couple of days it only detected 128. Yesterday I’ve updated bios to the latest release and seemed all fine, it detected 256Mb ram. But today ..surprise …it only detects 128MB. What can I do? I’ve tried to switch them in the slots but nothing.. sometimes it sees 192Mb or 128Mb.
Any suggestion?!
Tks

The only things I can think of would be hardware. Either some memory is bad, or you have a broken motherboard (either in a chip, a broken trace, loose memory socket connection or a failed socket).

Or you might be very lucky and just have dirty contacts. If a socket has been open for years, it can corrode a little - enough to give intermittent results. Clean the contacts on the memory, and on the memory sockets with alcohol and a lint-free swab (sponge-tip, not cotton) and see if that improves anything.

Get PC-Doctor from IBM/Lenovo's site and run the memory test. Also get memtest86 and run that overnight.

I've seen other 600X's with memory problems, and I think to really fix it, you'll need a replacement system board.

Hi,
thanks for your advice.
So I’ve tried by cleaning the sockets and for 1 day it worked but it stopped working after that. The memories are good I’ve checked them. I’ve tried also with PC-Doctor but it found nothing wrong.
What I’m trying to do now is to replace the 2 memories of 128MB I have with only one of 256MB and to put it in the good socket. Do you think it will work? I hope so!

That should work fine. Be sure your part is guaranteed to work in a 600X. It needs PC100 speed low-density SO-DIMMs. It should 16 chips, 8 on each side. PC66 will not work. PC133 is not likely to work, but it may.

High-density, either 8 chips all on one side or 4 on each, will most definitely not work.

Hi, I am having a similar problem, I think.

All of a sudden my 600x stopped working. I ran memtest and it fails in the first 15MB. I tried, just cause, to remove the 2 addon SIMMS that I had and rerun memtest...same thing.

Is it possible to get these machines repaired at the component level? If not, from where do you obtain a replacement motherboard?

Thanks for the help...Michael

It is not worthwhile to fix components. You can try your luck on eBay for a new system board. Be sure to get the right one (SpeedStep or non-SpeedStep) for your CPU.

You might instead disable the onboard memory by hacking the BIOS. Google should be able to find a resource for you.

I like the hacked BIOS approach, but I can not find anything on Google about it. Could you possibly point me in the right direction?

Thanks...Michael

Hi there UserTP600x

Just read your post & thought I'd try & help you out.

Try : Wims BIOS for the base memory hack, it,s under TP 600E Q & A @ www.wimsbios.com. Just register there with a user name & password.

I had a memory problem with my 600E the same as your's, which I struggled with on and off for days. Would work with 1 bank of RAM but not both. What I found was, the white plastic sticky protective cover under one of the sticks of Ram had lost it's stickness & come loose / bent forward. Pressed this back in it's original place & hey presto, problem solved. Must have been touching/shorting somewhere.