What could have caused this bizarre behavior???

[Muse]

I'm modding my main PC so it has HTPC functionality (It's Beauty in my sig). I'm still going to do a lot of other things with it, but I'm using it for HDTV tuner functionality. I also like to listen to music a lot, so as part of an entertainment as well as work (sometimes serious work) station, I want the box to be as quiet as possible. I was going to swap out the NVidia ti4600 video card for a fanless card but discovered that it is possible to run it fanless after installing a Zalman heat-pipe. I bought a Zalman ZM-80C heat-pipe and installed it Saturday afternoon. That's when some bizarre things happened.

I had problems getting the HSF off the GPU. The fan came off easily enough but the HS was stuck to the GPU pretty good. I tried to pry it off with a screwdriver but got nervous after applying what seemed like excessive force. I thought to myself: "I bet if I heat that thing up a little, it will come off easier and I won't risk damaging something." I decided to put the card back in the machine and turn on the machine for a few seconds (10-15 seconds). The HS was still on there, of course, offering some cooling to the chip and I didn't think it would damage it. However, when I started the machine, almost immediately there was strange information on the screen of my LCD monitor. There were a lot of zeros in vertical columns about 1 inch apart, and these columns seemed to scroll from bottom to top. Some (or all) of the normal boot information was also on the screen. When the Windows 2000 splash screen appeared, there were thin vertical lines flickering on some parts of the screen on and off, then the splash screen looked OK for a couple of seconds and then my monitor said "No Signal" and evidently there was no information coming from the video card.

I didn't know what to make of this. I figured it was just overheated, probably. Anyway, I turned off the machine and removed the card and the HS came off. I cleaned off the adhesive from the GPU, and installed the Zalman and put the card back in the machine and got the same crazy stuff when I turned the machine on. I went into the BIOS Setup, and things looked screwy. You could see the usual stuff, I guess, but there were additional characters. Some of the words were misspelled!

I figured the video card was toast and posted and people said "yeah, your card is toast." However, next morning I got to thinking: "The HS was still on it, only the fan had been removed. People's video cards' fans die all the time, and the cards don't fry in 15 seconds. What IS this?" I put the card in my other PC and it appeared to work fine!!! I put it back in my every-day PC and it seems to be working fine in it!

There's been no indication of any problem since (it's been two days). What happened? Thanks for your considered assessment.

 

[amdskip]

When you say you were prying with a screwdriver, what were you pushing against? I know when I removed the heatsink from my geforce 4, I used a couple old credit cards to pry against.

 

[Muse]

Originally posted by: amdskip
When you say you were prying with a screwdriver, what were you pushing against? I know when I removed the heatsink from my geforce 4, I used a couple old credit cards to pry against.

The bottom of the HS had a little clearance from the top of the GPU and I put the blade of a screwdriver in there and twisted it to exert upward force on the HS. Like I say, the amount of force I was applying was making me nervous, so I decided for the strategy of running the card a few seconds - enough to heat the adhesive some and I thought the chip wouldn't get so hot as to cause any damage. The behavior noted convinced me that it had indeed become damaged and unusable. The fact that it appeared to be working fine the next day has me thinking that something else accounts for the strange behavior noted.

 

[Cheetah8799]

The bottom of the HS had a little clearance from the top of the GPU and I put the blade of a screwdriver in there and twisted it to exert upward force on the HS

Maybe the edge of the screwdriver hit an electrical lead? might not be able to see unless you get the heatsink off completely.

Could also be that the card simply didn't seat well in the AGP slot when you powered up the rig. I've used mobos that have loose slots. I know on my main rig the DDR ram slots are really loose, and it makes me nervous, but I haven't had any problems yet... knock on wood...

 

[Muse]

Originally posted by: Cheetah8799

The bottom of the HS had a little clearance from the top of the GPU and I put the blade of a screwdriver in there and twisted it to exert upward force on the HS

Maybe the edge of the screwdriver hit an electrical lead? might not be able to see unless you get the heatsink off completely.

Could also be that the card simply didn't seat well in the AGP slot when you powered up the rig. I've used mobos that have loose slots. I know on my main rig the DDR ram slots are really loose, and it makes me nervous, but I haven't had any problems yet... knock on wood...

Oh, I got that HS off. Cleaned the GPU up nicely with acetone and installed the heat-pipe. There was no sign of damage.

I thought of bad seating of the card but it seems very unlikely, reason being that it happened when I put the card in after removing the fan and happened again after installing the heat-pipe. Conceivable but extremely unlikely, seems to me.