Can't figure this one out-weird!

handler-1

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OK I built a very nice Desktop PC for a student, or I showed him for his senior project. Basicly all Asus parts with an AMD CPU. Started with a good solid case and power supply. Here is what is weird- It is a complete system with LCD monitor and peripherls. So anyway it runs windows XP Pro and has no problem running at all at my house( plugged into surge protector) At his home the computer will not post or boot up and he will try for hours( had him buy a new srge protector after problem started but it continuied), once in a while it will boot up fine and then run great! So I brought everything back to my house and the very first time it posted and booted into windows without never once having a problem. Oh I had him purchase a new surge protector just to see if that may have been it- did not help. It seems to me that he must have some sort of power problem at his home but what? His other pc which is slow as hell starts just fine.
So it starts everytime at my house and runs very fast then at his home he will try for hours and maybe one time get it to boot. Do you have any Ideas, I would give you more specs on the PC if needed. It is basicly the same PC I build over and over for all clients except he has an add on video card. Also when he starts it the pc does not even seem to post, no video image is shown until he gets that one lucky start. Also I would maybe think of CMOS batter or bios but it works fine at my house. Tested power supply with LED tester and everything looks good. Ever run across something like this?
Hope you can help, Thanks Troy Hustead- PC Tech troy.hustead@gmail.com 707-272-7122.
 

orangegator

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Is he using all the same parts, including all the same cables, mouse keyboard, etc that you are? Has he tried plugging it into multiple power outlets in his house? To rule out the power from his house, he can plug the computer into a UPS battery backup. This would ensure it's getting proper power.
 
An LED tester cannot test voltage regulation properly.

I find it useful to think of a PSU as a buffer between the violent power coming from the wall (AC) and the calm power inside the case (DC). The more violent the power coming from the wall, the more troubles a poor or defective PSU will have buffering it.

A power supply is a very complex and important part of the build that should never be skimped, but even the best ones can be bad, especially if shipped from an online retailer and banged around on the truck.

Perhaps his wall socket is not grounded, or perhaps his power is just dirty, or perhaps his PSU is inadequate or defective. I have also heard of things such as RF interference causing issues.

I would try either:
- replacing the PSU with a higher quality one
- RMA-ing the PSU
- Buying a good quality UPS.
 

darkguset

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I don't think it is relevant, but i had built a PC for a client and at his house the computer boot fine, but after a few minutes the screen would go all crazy, when i took the computer to my office and another place later for testing, nothing would show up! Weird stuff, it took me about 10 days to figure out, the VGA was overheating and it was corrupting not only the graphics, but the Windows itself. By placing a fan on the VGA, solved the issue permanently. Now, why the VGA did not overheat in the other 2 places, and only at his house, that remains a mystery up to date.
 

2flow

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Ask your student if he has solar/wind in his home. Depending on how old his solar/wind system, he could have a modifed sine or even worse, a square wave. Most computer will run fine with a modifed sine wave but it depend on the quality of the inverter and also the quality of the PSU. If your student has a off-grid system, then he'll almost always have this problem. However if your student has an on-grid system. Then he should be able to run his computer only when the solar or wind system is off, meaning for a solar system it should work at night when the electrical grid kicks on while the solar is off. Or for a wind system, computer should turn on when there is no wind.
 

handler-1

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Thank you all for your feedback, yes pc is built with a very high quality P/S with 650 watts. I never build a PC even a budget pc without a quality P/S and I still always try to use a good quality case also so the pc has a good foundation for a build!!! I know that it is very important not to cut prices on your power supply. I Did check it in the bios one time and voltages seemed to be within an exceptable range.


I have been to his house and tried it myself. He is on the grid getting full power from the pole. I changed different plugins ect. COULD BE A POSSIBLE GROUND ISSUE ? also the two things I have not done that most have brought up is of course using a Battery backup supply (UPS).

But the other one that 2flow and orange gator mentioned, that I did not consider is that he is using an older mouse and keyboard that I never brought back to my house and tried with the rest. The reason why he is using it is because the new Logitech wireless keyboard and mouse set he bought uses a reciever that plugs into a usb port and also the old style I/O keyboard connection. In which the newer Asus board I used did not have the older I/O purple and green pin plugs for your mouse and keyboard. It's just loaded with alot of usb ports. So he switched it with usb wired keyboard and mouse that came from his moms pc. IT's posssible that thay may be causing it, but I never have ran across that before and they both work fine on the other pc. Whish I new the Asus model but cannot think of it right know. IT has a connection for HDMI, two RJ-45 ports ect. IT's a good board. He is using the onboard video right now until he can upgrade but it is a quality asus board tested and reviewed as a very stable board.
When we built it at my place I had newer usb keyboards and mouse. Never tried his setup that he switched with when setting it up at his home. So I can try those few things
Just talked to him this weekend and he says it seems to be not giving him as much trouble as before, usually second try it will boot. He said after it loads the PC is very fast and stable with no problems. Thanks for all your support, I will try what was mentioned and reply back to you all so you will know what I find out. Handler
 
I know this might not explain why it works at your house and only sometimes works at his house, but are the RAM speed/timings/voltage manually set to the manufacturers specs in the BIOS? Have you run memtest86+ overnight to test for RAM errors. A lot of times errors like this are caused by RAM problems. Just a thought.