Thinkpads Forum

Hi,
I bought last days an old 600e for my parents.The model is a 4Ax one (PII 366 Mhz,64 Ram).I wanted to update the RAM memory, so I got 128 x 2 SODIMM PC100 (in total 256).I know that the mainboard support only PC 66 but I found on some forums that some guys could use this kind of SODIMM module with PC100.
The problem is: my mainboard uses only 160 RAM (32 onboard and 128 RAM.)
I wanted to use all RAM memory (288 RAM or least 266),but the mainboard uses only 160.
The bios is last updated (http://www-307.ibm.com/pc/support/site. ... SHY-46HLKQ).
When I open the Config from Bios menu,the mainboard recognizes 288 RAM but it uses only 160.
I know also that I can disable the 32 onboard memory if I open (with Ctrl+D) the CMOS editor and I change the byte values from 2B (from 80 to 81).In this case I got less memory: 128 RAM.
How can I make a change in this editor (some bytes values changes) to use all RAM memory (288 or 256 RAM)?
Please help me!
Thanks in advance,
Alex.

Welcome to thinkpads.com!

Your 600E system needs to have "low density" memory modules. You can identify those modules by counting the number of parts that are on the modules. For the 128MB size, there should be a total of eight (8) parts; 4 on each side. 256MB modules will have a total of sixteen (16); 8 per side. There are some exceptions to this rule but if your two 128MB modules only have a total of four parts on them, then I would say that there is a 99.99% chance this is your problem.

The BIOS does not need to be edited in any way to allow use of these modules. You can enable the built-in 32MB again by resetting the BIOS or changing the 81 back to 80.

Hello,

Thanks for the answer.My 128 ram module has 4 parts per side (8 in total).It seems that I will use only 160 ram.
I dont know what else to do, only if I buy the right ram modules for my 600e.
Regards,

Alex.

I'm not sure what you mean exactly when you write the mainboard recognizes 288 RAM but it uses only 160. How do you know that it only uses 160MB?

I'm not sure what you mean exactly when you write the mainboard recognizes 288 RAM but it uses only 160. How do you know that it only uses 160MB?
when the laptop starts ,with F1 I can enter in bios->Config->Memory and here it shows 288 Ram installed (normally it shows in Kb something like 299.....) and 160 Ram used.

Don't know what to say.

My 600E reports 294xxx installed and 294xxx useable in BIOS.

OK, my 600e's bios reports somethink like yours, but only 160 useable.what kind of sodimm sticks do you have?

I bought them used on eBay.
They aren't even from the same manufacturer.
One is a Crucial 66MHz, CL2.
One is a Centon 128MBLT133.

Thanks for your details.Now I'm very confused, because I have 2x 128 Ram sticks PC-100 from the same manufacturer (I don't remember the manufacturer's name because the laptop is now to my parents).Could be the problem with the "low density" as rkawakami specified?

You need to look at the memory or have your parents look at them. It is very easy to do. All they need to do is have a small philips screwdriver and open up the memory cover on the bottom of the laptop. The laptop should be off of course. Just look. It is very obvious if there are 4 chips on one side or not. They shouldn't and don't need to touch anything.

It's possible one of the memory sockets is bad. Try using only one stick at a time. Then try the same stick in the other slot. The contacts could be corroded, and cleaning might fix it; or the socket could be broken, in which case you'd need to replace the motherboard.

Thanks for the advice both of you ieee488 and whizkid.
It's possible to be problems with one of the ram's stick and/or mainboard's socket.
I'll verify all these in this weekend when I will visit my parents and I'll let you know if I can fix that.
Regards,
Alex.

Hello all!
I have few pictures from the laptop with the ram memory sticks and also with the bios status.In this way I think that you can better see about what I told you already.
There are the pics:
1.The main bios status:http://www.w3axa.net/temporar/pentium2_bios.jpg
2.The 2 ram memory sticks(2x 128 Mb) installed on the mainboard:http://www.w3axa.net/temporar/2x128ram_installed.jpg
3.The ram memory bios status: http://www.w3axa.net/temporar/ram-memory_bios.jpg
4.Ram memory test from bios:http://www.w3axa.net/temporar/ram-memory_test.jpg
I will appreciate other advices from your side.
Thanks again in advance!
Alex.

Hmm... something does not seem right with the labels on the Micron memory modules. The part number "MT16LSDT3264AG-133E1" indicates that there should be 16 devices on the board, that it's a 256MB module (32x64) and it has been speed-rated as PC133. I can't see the actual part numbers on the individual memory chips but if that's really a 256MB module that has been marked as "128MB", then you really have "high density" modules and they will report 1/2 of the total capacity in a system such as the 600 series. I have seen a similar intentional mis-marking of 512MB modules as being 256MB.

edit: I'd say that a proper "low density" 128MB module from Micron would have a part number similar to "MT8LSDT1664....". The "8" would mean 8 parts on the board and the "1664" would be 16Meg x 64 bits wide or a total of 128MBytes. I would usually recommend that you get a memory diagnostic program such as memtest86+:

http://www.memtest.org/

and test each module by itself (only install one module at a time) but if the modules are indeed "high density" 256MB parts, then I don't think that you can effectively test them in a 600 system. You would need something like a T23 (if the module can still run at PC133 speeds) or a dedicated memory module tester.

ref: http://download.micron.com/pdf/numberin ... rammod.pdf (Micron module part numbering system guide; SDRAM on page 3)

Thanks rkawakami for all these informations.
You have right, my RAM modules seem to have speed-rate problems and also I couldnt done a memory diagnostic program with memtest86+.
Right now I'm looking for alternatives...to buy other RAM modules.
Regards,
Alex.