About 3 months ago when I was putting an old computer back together I accidently had the motherboard touching a piece of metel and two circuits crossed. When I turned it on (unaware) something close to the CPU chip started go up in smoke after only having the computer on for one second. This was while the motherboard was out of the caseing. Now my question is ever since then it has worked fine (after I put it back together properly) but I did not replace that piece. Will something happen down the road or is that ok that this happened.

motherboard smoke isn't good at all..i would guess your motherboard probably damaged..there might be some circults fried

Is it ok? No. If you turned on your TV for just a second and smoke came out of it would you continue to use it even if it worked just fine? Electronics and smoke don't mix. If you continue to use the system you could run the risk of fire down the road. I'm not saying it is going to happen but why take the chance when you no there is a problem. Be safe. KTTD

Probably what went up in smoke was one of the capacitors near the CPU. It isn't working anymore. If it was a resister or a chip or someother part, the system would not be working. The capacitor is there for filtering, not a major problem. I would look at it to see if it can be identified, and try to get a replacement installed. When you shorted the board you got too much current going through something, so smoke. You were probably lucky, since it still works. Be more careful, that's all. :)

I got a question on this also... I installed a stick of PC133 and PC100 in the same board and the DIMM started to smoke. There is a burnt spot on the RAM, but it works just fine. I am quite sure it is cauing the RAM to slow a bit. Of course i am running XP on a 400mhz PC with that 128MB and it goes fine which I find odd. But my real question is What would cause one to burn up while the other is fine? The speed differnce? ECC types?

What would cause one to burn up while the other is fine? A variety of things, a small conductive particle in the connectors, a damaged m/b (sound familiar?) The speed differnce? Speed diff isn't a prob, they will just both run at the slower of the speeds.

How To Build a PC - Electrical Problems by Billy Newsom Smoke and Electricity Years ago, scientists discovered the magic of electronics. Related to electricity, electronics equipment has one encompassing design similarity that has baffled men for many years. You see, electronics work on the principle of blue smoke. Electronics engineers trap smoke inside each discreet component in order to enable (or empower) it do wonderful electronic things. The problem is when an unscrupulous or inept person gets ahold of electronic equipment and attempts to do something which violates electronic dogma. When such a hideous act transpires, it is always indicated by what seems to be the production of a bluish-gray cloud of putrid smoke. This is known in the business as "letting the smoke out." When one lets the smoke out of a piece of electronics, it ceases to be electronic, and therefore it ceases to function according to electronic principles due to its lack of smoke. This is known in the business as "Smoke Theory." From MOTHERBOARD HOMEWORLD http://www.motherboards.org/build/build-32.html