600E (2645-5JU) Memory Limit - Moved from Marketplace

[virge]

Just moving this topic out of the Marketplace. To the Mods: I hope this is the right way to do this.

One potential issue: for some reason, the machine will only show 224mb total memory. I haven't been able to figure that out.

I know on the 600's, you need a pc66 in one of the slots to be able to read it fully. For some reason, one slot will read a pc100 stick at full capacity, but only half the capacity in the other slot. Maybe the 600E is the same???

Here is a breakdown of my experiments with my old 600

Slot 1 - 128mb pc100
Slot 2 - 128mb pc100
Built in - 32mb

Total = 224MB



Slot 1 - 128mb pc100
Slot 2 - 128mb pc66
Built in - 32mb

Total = 288mb



My last combo resulted in my max capacity:

Slot 1 - 256mb pc100
Slot 2 - 128mb pc66
Built in - 32mb

Total = 416mb

EDIT: After checking out the memory options page on Lenovos website, the only 600E's that were pc100 compatable in both slots were as follows, and the latest bios had to be updated too:

Requires BIOS version inet26ww or later
Compatible with 600E 3Ax, 5Ax, 5Bx, 4Ax, 8Ax, AAx, 4Bx, 8Bx, BAx models only.

http://www-307.ibm.com/pc/support/site. ... WIK-3TLS8K

So that is why your old 4B board worked, but not the new 5J board.

The onboard 32mb is PC66 so that was disabled in order to upgrade the CPU. You would think that the memory displayed would be 256MB if both sticks were recognized or 192MB if only half of one stick were recognized.

Maybe somehow disabling the 32mb onboard disables 32mb of one stick? I don't think I have any PC66 larger than 64mb to try.

Interesting. Sorry to take this FS thread off topic and turn it into a troubleshooting topic. But....

Have you disconnected the CMOS battery at all since you disabled the OB RAM? If so, it may have turned itself back on. I know with a 600X I was testing, I turned off the OB RAM, but it came back on after unplugging & re-plugging the CMOS battery. Just a thought. Maybe check to see that it is still disabled?

Wingnut: Apparently my biological memory is failing me... I checked the bios hex editor and the onboard memory was NOT disabled. Byte 20B had "81" in it. I changed it to "82." Now it boots up and Windows shows that 256MB memory is installed! This is with PC100 memory. Maybe give this a try in your TP600 to see if that enables both sticks of PC100. I'd be interested to see the results.

[Wingnut]

Very interesting. Unfortunately, I no longer have my 600, but that is good information to have as it can increase the usable RAM on these machines if it works.

[rkawakami]

This may apply: http://forum.thinkpads.com/viewtopic.php?t=51580

This was with a 600 (not 600E) system but my guess is that you need to use a single bank module in the front slot to order to be able to "see" all of the memory. It's an issue about what type of memory parts have been used and the design of the module itself.

[tfflivemb2]

Ray,

I believe that this issue was somewhat solved in the FS ad. It turned out that the OP had NOT disabled the onboard ram. Once the onboard ram was then disabled, the remaining ram appeared.

[virge]

This may apply: http://forum.thinkpads.com/viewtopic.php?t=51580

This was with a 600 (not 600E) system but my guess is that you need to use a single bank module in the front slot to order to be able to "see" all of the memory. It's an issue about what type of memory parts have been used and the design of the module itself.

Ray,

I read through that thread and if you're still looking into this issue maybe this data will be helpful. The installed memory is one PC133 module in the slot closest the outside of the machine and one PC100 in the other. With onboard memory enabled, it was running with no problems but showing only 224mb memory. With one module removed, it showed 96mb. After disabling the onboard memory, and installing both modules the machine displays 261mb at boot up and Windows shows 256mb.

Andy