help! SDRAM problem

[andreadebiase]

I have a system running smoothly with 128 Mb SDRAM 133MHz. I purchased from the same supplier an additional 64Mb (133MHz) and started having booting problems. First of all you may know that both dimms are fully recognized in the bios so i guess there is no prob concerning installation but when it comes to load Win98SE, after a while, the blue screen comes up telling me there are system registry problem that windows is trying to fix.....well after hitting the enter key to fix these probs the system prompts me again with the same message for another few times (same thing in safe mode). Only once I got a total fatal error and ONLY once Win loaded perfectly (the very first time after adding the 64Mb) until i restarted the PC and the problem showed up again. If I remove both dimms and put the new 64 dimm, ALONE, in place of my old 128 dimm, Win loads perfectly (the 64 dimm is healthy!!) and if then I add my old 128 dimm I get problems again. Basically these two suckers don’t seem to like eachother and the system gets crazy. The technical staff where I purchased my 2 dimms told me that there might be a difference in CAS latency time between the two dimms (one is 2 and the other is 3) and this might create the prob so I changed the settings in the bios asking the system to make use of CAS3 only but nothing changed. Plus, the memory chips on the dimms have a code number and in the MICRON site i was able to verify that both dimms are CAS 3 so there should be no CAS conflict.
These are the # on dimm 128Mb 133MHz: 48LC16M8A2TG -75B
these are the # on dimm 64Mb 133MHz: 48LC8M16A2TG -75B

i am not an expertise in SDRAM, can anyone tell me if these two are compatible? or what else is going on? do i have to re-install Win98SE everytime I add a new SDRAM module?
thanks

[Fish]

I don't have the answer,but it seems to me that if they both work good seperately,but not together that somehow they have to be uncompatible.
Have you tried putting the 128 in the first bank and then the 64? Then vice versa? Sometimes certain mobo's require a certain order.

And no you don't have to reinstall windows every time you add memory. Someone more knowledgable than me will come up with the answer. Hang in there.

[This message has been edited by Fish (edited 03-15-2001).]

[Reid]

I've had the problem of PC133 DIMMS not working together. I just reduced the memory speed to 100MHz and lived with the performance drop, which is not significant for me. I buy cheap memory, so I could blame myself if I was inclined to.

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reido@my-deja.com

Friends don't let friends install Windows ME

[andreadebiase]

yes, i did try all the different combinations (1st 64 then 128 and viceversa) but nothing changed. I don`t know if the memory i have is cheap, is Micron brand what do you think?

[Fish]

I only know about crucial.com But I've never heard anything bad about Micron. I've been doing extensive searches for you on this ever since I posted, and can't for the life of me come up with anything. Hope something comes up soon for you.

[Reid]

What brand and model is your motherboard?

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reido@my-deja.com

Friends don't let friends install Windows ME

[andreadebiase]

Mobo is FIC AZ11E, memory is Micron.

[andreadebiase]

should i try with the "load safe settings" in the bios?

[BigBlue66]

Well, it's just a shot in the dark here for me, but are you completely sure that both sticks are either both buffered or both unbuffered? No, I don't know how to tell. Maybe Randy or Pete will have an idea. Seems though, that if the CAS lacencys are the same, speed is the same, they're both good otherwise, you have tried all different combinations, that either the problem relates to buffering or a parity issue. Have you tried turning off ECC checking in BIOS? Or maybe you have a line item that says something about parity checking. Is that enabled or disabled? If it's enabled, try disabling it and see what happens.

Sorry I don't have a more conclusive answer, just shooting from the hip.

Good luck.

Big Blue 66

[bassvax]

I found this program on a gaming site I believe. I downloaded it and the interface is in English. It is provides the most comprehensive information regarding your DIMM that I have seen. I have Sandra and she doesn't hold a candle to the info you will find with this program. http://www.heise.de/ct/ftp/ctspd.shtml
Luck be with you http://www.PCGuide.com/ubb/smile.gif

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Jerry

[Paleo Pete]

I can't think of anything that's not already covered, but I think BB is real close. Buffering or parity issue sounds like a very good possibility to me.

Micron is supposed to be a good brand too...

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Eagles may soar, but weasels don't get sucked into jet engines!
Note: Please post your questions on the forums, not in my email.

Computer Information Links (http://www.geocities.com/paleopete/)

[Randy_tx]

I've seen it many times before.....both sticks work great independent of ea other and NOT together......It's over my head for sure http://www.PCGuide.com/ubb/biggrin.gif

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"As hard as a rock & dumb as a brick"...Windows CEMeNT

[andreadebiase]

I decided to return the 64Mb stick and ordered a 128Mb that is supposed to be identical to the one I alredy have. If the newest 128 does not work I`m going to return all my memory and buy another brand. Boy!!! I really would like to know what caused the problem though, I also loaded the safe Bios settings and still had the problem, actually i had a new simptom, a very long beep (Award bios) while Win was almost done loading.