Computer was power cycling, turning on and off

Hey i have a bit of an issue with a customer's computer. He told me that the monitor it self was not turning on and that it only receive a black screen with a yellow light indicating that this could be a video output problem. How ever he also told me that when he turned on his computer, it would power cycle off and on some times multiple times and keyboard would not light up. Obviously if your having a power cycling issue like that, then none of the plug and play USB's are going to work. Now when he brought the computer to me. I turned it on, the first thing that happen was exactly what he described, black screen, no video output so i switched out the cable for a VGA cable. it came up with an error message stating that the "bios clock setting was not set" or something similar to that. I tried to isolate the problem as much as i could, at first unplugged the DVI cable and plugged in a separate VGA cable that i used with another machine to see if the cable was bad, it worked, the screen came on and everything seemed ok. When i plugged the DVI cable into another monitor, it literally scrambled the other monitor for some reason. So it looked to me like it was a cable problem. Then suddenly when i reset the computer, plugged the VGA cable back into the conflicted monitor, the computer it self started power cycling, turning off and on like bout 3 times. So i started thinking what the heck can that possibly be? The only indication was that error message stating that the clock setting of the bios was not set. Now mind you this computer is very new, it has new parts and the video card i bought bout a few weeks ago. Also if it was a video card issue, it would be having the same problems plugged into another monitor but it wasn't. So that indicates that the video was not an issue. I think personally their were two separate issues here, it might of been a touchy bad cable, but the power cyling of the machine could of been caused by the computer's bios being over clocked. That is what i think anyways. For some reason right now, its actually working with both cable's, i don't know what i did, but it seems ok. But i am concerned bout how the machine power cycled like that and i do not want that to happen again. So is their any information you can provide, i was thinking bout "flashing the bios". Do you think that would fix the issue, how would i go about flashing the bios, i do have the disk with all the drivers on it and one of them is a installer that flashes the bios, which resets everything to its default value. I also have alot of MSI tools on the machine that the motherboard came with to help diagnose problems and perform perform maintenance, check clock speeds, temp gauges, etc. I don't believe this was a power supply or graphics card problem, causeless the PSU is well equip ed to handle all of the components and wattage capacity of the computer and the graphics card is brand new, i just bought it like a few weeks ago because the old graphics card in the machine went out, in fact i had another topic discussion on here related to that problem in which i fixed. The customer which is my uncle btw told me that he has alot of friends over their that mess around on his machine, and his bios was not locked. So it really looked like to me that some one tampered with the bios settings inside the machine. Another indication of this was his password had been removed. So please give me your thoughts on this matter and what I should do at this point, thank you! A little more information that might help you diagnose this issue. The motherboard is a MSI P67A-GD65B3

TBH with that amount of power issues I would put a meter on the PSU, it goes deeper than the PSU being man enough, all those power issues make me suspect it has had a power surge, and if that is the case then it could of taken any number of components with it, or even all of them in the worst case, so I would not mess around with any single part at this stage, I would ensure the PSU is performing correctly, because if it isn't then nothing else will behave either, not to mention if the PSU has gone bad, you don't want to use it on ANY system, as it gives more opportunity to do even more damage, so check that out is my advice, also see if they have any surge protection, and ask if other items work fine in the socket the PC was using, it "may" be house wiring affected, see what this tells us and go from there.

Well thanks for the information, i had already started working on it before i saw this post, but i think i fixed the problem. I went into the motherboard, i removed the battery and resetted the CMOS jumper and apparently that fixed everything. Everything seems to be running fine, its not having any power issues and its booting normally. I think maybe the power cyclying could of been because some one screwed out with some settings inside the bios. Is that a possibility to cause that kind of a problem? Because right now its working great after resetting the CMOS and replacing the battery on the motherboard.

Yes that was the next step, it's amazing how much chaos that little battery can cause, but not knowing the details we have to go with priority's, and the first one is protecting what there is, and as power was a concern, it had to be ruled out, just incase it caused more damage, next would be a new battery again as it was power related, then if all that made no difference you start swapping parts in\out to prove each bit in turn with known working hardware, but it's great news it was a simple thing lol. But it's still good practise to use surge protection, if they have none, it would be a wise investment.

Yes that was the next step, it's amazing how much chaos that little battery can cause, but not knowing the details we have to go with priority's, and the first one is protecting what there is, and as power was a concern, it had to be ruled out, just incase it caused more damage, next would be a new battery again as it was power related, then if all that made no difference you start swapping parts in\out to prove each bit in turn with known working hardware, but it's great news it was a simple thing lol.

But it's still good practise to use surge protection, if they have none, it would be a wise investment.

Yeah the user does have surge protection. But what happen was some one went into the bios and changed the clock settings, because that does not happen automatically. I know some times i just can''t figure out how computer's work. I mean even if your a certified tech you still run into minor problems such as when i took the battery out and replaced it and then reset the CMOS jumper. The screen was a black for a while, it just didn't work. Then i reset the computer a few times and eventually it just popped on. Explain that? Some times that happens when you ever doing like a hardware change, its not always perfect. Maybe their was just a delay, i had to wait a certain amount of min before i plug the machine back in after resetting the CMOS.

Some times things just happen that way and are just unexplainable.

Well if someones entered the bios you need to ask why, you could password it, but the danger is forgetting the password, or it becoming corrupted, but the battery doesn't surprise me, there are components within a system that can hold a charge for a short while after removing power, and although using the "Clear CMOS" setting which should be enough, the belt and braces way is to remove the power lead, even if the switch is turned off on the wall. Then remove the battery and set the jumpers to Clear, then leave it 30 seconds to 1 minute (I once had to wait overnight on a nightmare system), then it should be completely reset, needless to say, use static caution when touching parts, and always remember, just because an electrical device is unplugged from the mains, there may still be enough power retained to kill you, in a PC this would be inside the PSU, so as your no doubt aware (only mentioned for others not as knowing) always use caution.

Well i can't believe i am replying to this thread again but umm it appears he started having numerous problems and i took out his video card and placed it in my computer and it did not work. So problem is at last isolated, its the video card. A card that i bought maybe 3 weeks before it was even used, im using a 550 WATT PSU OZY which should be way more then enough to handle that card. The card is a GTX550 TI. He has nothing in that computer really that is using alot of power besides that card and it only uses one power source, unlike my card in my pc that use two power sources. So is it possible that if some one went into the bios settings, could of use the over clocking settings to destroy the graphics card, because its not working, its completely dead. I get no video output signal what so ever and the monitor just goes to sleep. Before when i was testing this, it work fine, so i figured maybe it was a bad cable when i switched the cables, but apparently that was just a coincidence, it was slowly dying i think and now its just finally dead. So i want to take it back and get a different card, do you think its possible with my current build, that the card was to powerful for the pc? I just don't see how that would be a problem though having a MSI P67A-Gd65 mobo, a 550 watt OZ PSU, and i checked all the temps and they are fine, nothing is over heating or anything like that. I am just curious what could of possibly destroyed that card in a matter of a few weeks. My uncle did say that they did have power outs frequently because of the snow storms, but he had it plugged it into a surge protector so it should of been fine.

Again I would check the PSU, if only for peace of mind given it's all been power related, and make sure each of the rails are outputting the correct power tolerance for each line, but they do say a 400w upwards PSU as meeting the requirements, but just check the specific lead supplying the card is supplying the correct amount of power, also watch out if there is more than 1 lead that will fit, I've had a PSU where it had a number of leads that would fit, but only x number were the ones that worked.

As to failed overclocking, I couldn't say for sure, I don't have a deep enough knowledge in that area, but generally speaking failed overclocking can kill components, but I can't say if it could affect a video card, RAM and CPU certainly, but I can't recall if there are video settings as well, I don't think there are any, but I could be wrong, but my gut says unless the card was overclocked directly, and nothing to do with the bios, then yes thats possible.

But the power surges concern me, a surge protector does a great job of protecting the system within it's ability's, BUT, they don't catch everything, also you need to ensure that EVERYTHING that goes into the PC goes via the surge protector, eg obviously the mains plug for the system is put in the protector, but you also need to cover other connections, eg if there is a phone line connected, that needs to pass through the protector, probably the same with the router.

My understanding is if it's connected to ANY kind of power source, it needs to pass through the protector, if it doesn't then some may say it may as well not be used, but any cover is better than none, but if they can afford a UPS device it is much better and covers a greater range of power fluctuations that could cause damage compared to a standard surge protector, so is a wise investment.

Surges are not predictable, nor is the damage they can cause, it's a lottery, which is why only some parts are affected, or the entire system can die, but about the only thing I can suggest given the lack of life in the card, is maybe reseat the heatsink on it, if the card is too hot it wont work, and although very unlikely, given the apparent demise of the card, it can't hurt to check, slim hope is better than no hope, but if the card is dead then a new card is the only solution, but if you haven't done it already, a reset of the bios would be a good idea just to reset anything that may have been changed, hope this helps a little anyway.