Pesky SDRAM installation problem on K7VZA mainboard

[joea64]

I'm having some trouble successfully installing a total of 512MB of RAM, in two 256MB PC133 DIMM's, on an ECS K7VZA mainboard (where the CPU is an AMD Duron 800, the system bus is 100 mhz - and the RAM is also set to PC100 in the BIOS - and the operating system is Windows 98, 2nd edition). Actually, the problem is not so much that the system won't see the memory - it will, which is part of the puzzle - as that Windows is apparently choking on it and Norton Diagnostics is claiming errors in testing memory when both DIMM's are present on the board.

Here's the situation. This particular board has 3 DIMM slots. Right at present, one 256MB DIMM is installed (properly seated and locked) in DIMM slot 3, the farthest away from the CPU. The DRAM timing in BIOS is set to the default, SDRAM 8/10 ns, and the DRAM clock is at PC100. Norton Diagnostics (from Systemworks 2001) reports that the DIMM passes the memory test, and it works satisfactorily on all tasks, including multitasking.

The problem comes when I attempt to install a second DIMM, same capacity, same manufacturer, in either of the other slots. POST at system boot recognizes the SDRAM, and Windows also sees the whole amount of RAM when it starts. However, something is going wrong somewhere along the line, because, as I said before, Norton Diagnostics claims an error in testing the RAM when both DIMM's are installed (even though _both_ DIMM's check out OK when they are individually tested), and strange memory problems such as running out of system memory crop up when they should not because of the amount of installed memory, after only a few minutes or hours of operation. Cleaning the contacts and moving the second DIMM around to a different slot don't solve the problem. Frankly, I'm at my wit's end and half-inclined to give the whole thing up as a bad job because 256MB RAM is already an ample amount of memory (yes, I've optimized the swap file and created a disk cache in system.ini).

Has anyone else run into similiar problems, and if so, what have you done to solve them?

-Joe-

[mjc]

Ok, once again into the breach my friends....Win9x has a problem with memory when it approaches or exceeds 512MB, it basically chokes on it...here (http://support.microsoft.com/support/kb/articles/q253/9/12.asp?LN=EN-US&SD=gn&FR=0&qry=512%20RAM&rnk=2&src=DHCS_MSPSS_gn_SRCH&SPR=W98SE) and here (http://support.microsoft.com/support/kb/articles/q181/8/62.asp?LN=EN-US&SD=gn&FR=0&qry=512%20RAM&rnk=1&src=DHCS_MSPSS_gn_SRCH&SPR=W98SE) are some links from MS dealing with this.

If you have run through those then if you really want that much memory you can try 2 128MB sticks...


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mjc
Links list:Computer Links (http://www.dreamwater.org/tech/mjc/index.htm)

Celts are the men that heaven made mad, For all their battles are merry and their songs are all sad.




[This message has been edited by mjc (edited 09-27-2001).]

[joea64]

OK, I've done that. As a matter of fact, I own two machines and I've been running a disk cache on the older one for months. That machine has 64 MB and the cache is set to 8 MB, which seems to be about optimum. However, although most sources say your optimum disk cache should be 1/8 of total system memory, there are others that say that the cache doesn't need to be larger than 16 MB in any case (which is what I have set on the other machine, the one at discussion). What should the optimum disk cache size be for 512 MB?

(The MS Knowledge Base article also mentions MSCONFIG, which I have a shortcut to on my desktop now, and limiting the actual amount of RAM that Windows can use, which I will if I keep experiencing problems, and also checking the AGP aperture, which is set by default on my system BIOS to 64 MB. I have just tested the system after reinstalling the second DIMM, and things are seeming to be working better; the only problem I encountered was when I tried to run PowerDVD with Norton System Doctor running in the background, but then PowerDVD requires a lot of memory anyway; when I turned off System Doctor and restarted PowerDVD, the program worked OK and I was able to close it and then start a fairly memory-intensive game, Civ II: Test Of Time. Couldn't do that before setting the disk cache.)

-Joe-

Originally posted by mjc:
Ok, once again into the breach my friends....Win9x has a problem with memory when it approaches or exceeds 512MB, it basically chokes on it...here (http://support.microsoft.com/support/kb/articles/q253/9/12.asp?LN=EN-US&SD=gn&FR=0&qry=512%20RAM&rnk=2&src=DHCS_MSPSS_gn_SRCH&SPR=W98SE) and here (http://support.microsoft.com/support/kb/articles/q181/8/62.asp?LN=EN-US&SD=gn&FR=0&qry=512%20RAM&rnk=1&src=DHCS_MSPSS_gn_SRCH&SPR=W98SE) are some links from MS dealing with this.

If you have run through those then if you really want that much memory you can try 2 128MB sticks...

[BigBlue66]

Hey,

Well, this is certainly interesting. I had the exact same problem with a Micronics C200 board. After every possible combination of memory sticks, I concluded that I had two bad DIMM slots. I was also using NSW 2001 to test the memory!

However, at the same time I was getting reported errors from Norton, no matter which combo of memory I was using at the time, I was getting the dreaded BSOD and lockups. She would freeze up tight and I would have to press the reset button.

I finally concluded that the DIMM slots were bad, all three sticks of memory I had were good, and chose to just use one 256mb stick of memory. After that, everything was OK.

MJC has pointed you to a possible workaround that may just work. I didn't think of that when I was having all my problems. Wish I had.

Anyway, I'm beginning to think there is some sort of idiosyncracy with NSW 2001's diagnostic program. Especially if your system seems to be working OK other than the reported memory errors by Norton. On the other hand, if you are experiencing what I did, such as lockups, freezes and BSODs, then you may very well have bad DIMM slots as well.

The reason I'm thinking that Norton is choking or something, is that I have another machine that has two DIMM slots for a total of 512mb supported memory. Norton also reports errors when I have both slots filled, but, I was not getting any other errors or lockups. The machine runs fine, even though Norton insists that there are memory errors. Go figure.

Keep us informed on your progress and I hope some others have an idea or two.

Cheers,

Big Blue 66


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"Right turn Clyde!"

[joea64]

Just got home, and I took the time to try a DVD again in the drive. I turned off System Doctor first, according to the old principle of "well, then, don't -do- that!" (Like in the hoary old joke, since it's apparent that PowerDVD and System Doctor don't like each other.) DVD playback works perfectly, including audio (apparently I had the cable switched around so that the "red" cable was in the wrong place. That's something none of the books ever seem to mention...)

I'll try some more applications later this evening - Europa Universalis, for example, which has fairly hefty memory requirements - but I think I might have gotten this licked, at least partially. The key will probably be finding the right disk cache size and tweaking the amount of memory visible to Windows in MSCONFIG.

I agree that there's probably some kind of idiosyncrasy in NSW relating to memory; in fact, I'm wondering if there's a patch to NSW which will fix that particular test. I don't _think_ the DIMM slots are bad; this is a brand-new motherboard, installed right out of the box less than two weeks ago. I'd been having freezes _before_ setting up disk cache, which makes me even more sure that MJC is on the right track. Haven't had any lockups yet, but then I need to find something to push the machine really hard with.

-Joe-