EMI?

amplifier causing corruption…?

Hello!!!

I have a JVC home stereo amplifier rated at 80W/channel sitting right on top of my rackmount server case. I’m continually getting problems with corrupt system hives and stuff on my computer… it only seems to happen every time I move my computer, so I’m thinking possibly bad cables/IDE controllers,
since I’ve run every possible test on my hard drives and they’re
reported as just fine… but could EMI from the amplifier cause this? I know when I had the amplifier sitting under my monitor, the picture would shake and wobble and stuff. I put some aluminum foil right under the top cover of the computer
case and made sure it was grounded - would that make a difference?

Thanks!

Not an expert here, but I imagine the chances are very very slim that EMI would actually cause data corruption to reach the drive due to the CRC error checking done on the data for UDMA drives. So corrupt data would cause slowdown (due to data not checking out and thus, being retransmitted), but not corrupt files–unless you’re very very unlucky…and if I’m lucky, someone will do the math for me and give you a more meaningful interpretation of that statement. :D I did some quick googling, and read that CRC was introduced with UDMA, so if your drives are running in PIO mode for some reason, there would be no CRC protection. But I’m not sure what level of EMI would be necessary to actually affect your IDE data, so I’ll leave that to the experts. Hopefully one will intervene here and shut me up! :D

Tony

OK… that sounds pretty reasonable.
Yea I’m running UDMA on both drives. I disabled write-behind caching, knowing that that could possibly cause some problems. The weird thing is that this only seems to happen when I move the computer! It’s a rackmount case in a rack (as it should be), very sturdy… I don’t know exactly what this is!! Last time it happened, I got STOP errors of every kind of description even while formatting and reinstalling Windows. I reseated the sound card, RAM, and unplugged and re-plugged the hard and CD-ROM drives, and that had it working just fine for a day… when the system hive went missing or corrupt!! I brought it back home from where it was at, and now it’s just fine… I’m a Windows XP support technician by trade, and I’m shaking my head over this… well I know it’s not XP, it has to be hardware (which is not my specialty)… OK I’m just rambling on at this point.

Any other advice or suggestions would be greatly appreciated.

I had a similar issue a couple of months ago that caused hard drives to get corrupt on an apparent random basis. This ended up being a memory seating issue, so perhaps you could try re-seating it again or trying another set (I’m also a system engineer and this one had me going for days).

Memory seating - interesting. I guess I could try moving my two chips (two sticks of 512MB PC3200 Infineon RAM) to the other two slots, and find out if that helps. I let Memtest86 run overnight just now, and it went through 24 passes without any errors - at least the RAM itself is not bad!

I’ll keep that one in mind.

OK

I emailed JVC and asked them what kind of radiation I can expect from the amplifier… although the memory seating issue sounds a bit more likely because, as I mentioned, it only seems to happen when the computer gets moved from location to location. Luckily I keep my ghost disk handy and sometimes my ghost backup can fix it :)

Any other ideas?

Yes, that sounds about right to me.
Test and isolate (sigh)… O the continual bother…

Thanks for your help guys.
Ryan

aluminium foil
Good for rabbit ears and alien protection hats.

It also looks kind of cool - really shiny and stuff.
ooooooohhh… :D

Eh I tried puttin 'em on a rabbit once. It didn’t like it…

TG