Hey guys, have a really odd problem on my hands: I was halfway through installing some LED's in my case when I accidentally shorted the 12v and ground cables (exposed, not heatshrinked). The pc immediately shutdown . When i attempted to restart the system, the CPU and Case fans would spin for a few seconds then reboot again, etc etc. Figuring that this was a power supply issue, I bought a new one, installed it, and the problem continued. My motherboard had previously been iffy, so i decided tor replace it as i figured that surely if the problem was not the PSU, it must be the mobo. Just finished installing new mobo and the problem remains. Have tried different ram and that does not help. So that in itself it is not that bizarre. But when i removed the 6pin connector on the video card (8800GTS), the system now emits a strange screeching noise and keeps going on its reboot loop. I don't have a case speaker installed and I have tried two different mobos and the sound is exactly the same. Question is: what is causing the screeching sound (it only happens when the 6pin is unconnected) when I have no speaker inside my case? I imagine that diagnosing the screeching sound would allow me to replace the part which is not working (only thing that i haven't replaced now is the CPU). Any hints/ideas/suggestions?
The screeching sound is probably capacitors on the video card. Can you borrow another GPU to test? If you've replaced mobo, PSU and RAM and it still doesn't work, everything seems to be pointing towards the GPU.
get a speaker for the case. The beeps that it issues when there is a problem are problem specific. The number and type of beeps tell you what the problem is. Also try another GFX card just in case its the card that is faulty. Failing that fall back on the old failsave remove everything except one stick of the memory and the gfx card and the cpu and see it it boots if not then the problem is with either the mobo (which you've already replaced), the memory (again which you've already replaced), the cpu or the gfx card if it does boot then start adding things back in one at a time until it refuses to boot.
Thanks for the speedy replies. Just tried booting the PC without a GFX card, did the exact same thing without the screeching. But do GFX cards normally screech when they dont have the 6 pin power supply in? Its moments like these that make me want to ragequit computers lol
I did it initially just to see what components might have been causing the system not to boot. When it made the screeching sound I thought that the GFX may have been the cause of the problems.
As already said... reconnect the 6pin.. connect a PC speaker to the mobo, and find out what the POST error code (number and order of bleeps) is from your manual. That will tell you exactly what is wrong.
I forgot to connect the six pin to my old X1950 Pro once after changing the cooler on it and I didn't have any problems after realizing my mistake. I also fitted a 6600GT for a friend which required extra juice via a molex connector. It booted but I got a warning saying it needed more power. So I connected it and all was okay. Depending on the card I should think it wouldn't start. As you know the PCI-Express slot can only supply so much power
+1 Not sure you can damage the GPU without power connnected. Most GPU's will put out the same 'not enough power' message Ady mentions as far as I'm aware. Shorting power across a running motherboard can have all sorts of undpredictable issues though as the power release and delivery through the short is way in excess of what can be handled by most components. Horrible to think that installing some LED's can nuke your system to such effect.
