Strange RAM behavior

[bairdjc]

Sys config:
Soyo Dragon Ultra (KT400) (about 1 week old)
Athlon 1.4 GHz
512 MB PC2100 SDRAM (2 sticks of 256)
XP Pro
WD 120 GB 7200 RPM HD (model?)

This problem has me baffled! It started with my system randomly restarting one night. So, it restarts and gets to the windows boot screen. Then it restarts again. So, upon restart I go into the BIOS to make sure everything is OK. Everything is fine so I reboot. Upon reboot I notice that the BIOS reports 384 MB RAM. Well, I have 512, how does that work? So, XP complains about some corrupt file that needs to be repaired (with recovery console). So I reboot, select “Last Known good configuration” and XP boots fine.
About 2 hours later I reboot. Upon reboot BIOS reports 512 MB RAM. Good. XP won’t boot, says something about ntfs.sys being corrupt. So I reboot and try recovery console a few more times. On some of the boots, I get very strange intermittent hard drive sounds; it almost sounds like the hard drive is spinning, then is stopped abruptly (with almost sort of a little click) and then spins back up. So, I shut down and do a cold boot. System recognizes 384 MB system ram. Go into XP boot menu, select last known good config, and here I am typing. What is going on here? At first I thought that it might be some RAM going bad, but then with the boot problems later I begin to question that result.

However, tell me if my reasoning is right (I don’t know details when it comes to memory). Perhaps the memory is in some sort of metastable state where sometimes it reports as 512, and others it reports as 384 (one of the modules reports 128 instead of 256). Well, on bootup the system loads some files into memory and then reads them from there. If the memory is metastable, then at one point in time Windows could “store” some of any given file in the “bad” part of the ram and some in the “good” part. Then when it goes back to read it, the bad part cops out again, and windows sees the file as corrupt. This would also explain why I am not getting the same file everytime I start the machine (sometimes it says ntfs.sys, and sometimes it’s a system directory, and sometimes it’s another file). Also, if I am in windows now, then the file(s) and directorie(s) aren’t corrupt, so something is fishy here.
Does anyone have any ideas about this problem? I just got this motherboard a week ago (actually I upgraded from an ECS K7S5A, because it was giving me problems), so I’m pretty sure it’s not that. I am REALLY leaning toward the ram, however.
Any ideas?

Thanks in advance;

 

[Crashman]

I had this same problem on anther Soyo board with top quality Crucial SDRAM. It turned out to be capacitors. Soyo used some bad ones, and they hadn't completely burned yet. The unstable voltage was overheating my RAM, and one stick would loose one side, dropping me from 512MB to 384MB. Having a super stable Win98SE installation, I could boot on that into windows until another error happened, reboot, and find the OTHER module lost one side too, leaving me 256MB!

Now, the heat buildup was mostly in the poorly ventilated space between the modules, so I guess those were the sides that failed first. But later on, my motherboard exploded (yes, that's right, I said EXPLODED) when the bad capacitors shorted out!

Anyway, that just goes to show you that it WAS a memory problem but that the memory problem was a result of a motherboard problem. So do you have a bum module or a bum board? I don't know yet, try removing one. If that fixes it, try swaping the other one in. If you still don't have a problem, it's most likely heat that's affecting them.

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[nausicaa]

hard drive clicks? back up NOW to be safe.

"to start press any key..."
where's the ANY key?

 

[bairdjc]

Thanks for the great post. You know, the heat issue does make sense. If you live in the northeast you'll know that for the past week we've had a cold snap, and consequently my fiancee decided to make the apartment a furnace (heat turned way up). So, the ambient temperature was definately high. On top of that, when I had the strange RAM count problems, I had just viewed a 2 hour movie on my DVDROM, so that probably added to the heat issue (the drive is practically right over the RAM bank). Also, before then, I had had no problems with the board (it's brand new).

After I posted the original question, I removed the secondary stick of RAM. So far I haven't had any problems. Windows and everything works fine. I haven't tried switching out the other module, and I don't think I will. I ordered some mushkin last week, so I'll just replace the stick.

Usually the case doesn't get too hot. The hw monitor that was included by Soyo typically reports case temps around 37oC and cpu temps around 47oC.

So you think the new mushkin will resolve this problem? The new stick has a heat spreader on it. If not, I'll get a small fan and install it somehow to blow onto the ram lengthwise.

Thanks;

 

[Crashman]

You can find RAM cooling kits at some stores, they use a small fan that clips to the RAM chips, and include heat spreaders.

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