Computer Boots At My House, Not At His!

Hello Everyone,

I am a computer hobbyist/technician who fixes computers on the side for some fun money. I also earn my paycheck as a technology director for a local school district. I have recently become baffled by a certain customer's problem. I originally diagnosed a bad power supply and replaced it with an aftermarket part. The computer is an EMachines desktop, and after giving the fixed computer back to the customer (I did several hours of post-testing after the new power supply was installed to ensure that the fix was successful), he can't get it to boot at his house. He even showed me a video of it failing to boot. When he brought it back to me for continuing repair, I booted it right in front of him at my house and it works perfectly.

I have trolled the threads in majorgeeks.com, and most similar discussions involved wiring/grounding or people asking the originator of the thread whether the memory is properly seated. Can anyone offer me an explanation as to why the computer would not work in his home, but it works perfectly in mine?

Thanks in advance.

 

go to his home and see for yourself; maybe the answer will be obvious to you when you actually see it not boot

 

Greetings, pbrackett, and welcome to MajorGeeks...

Interesting problem. First thing that comes to mind, of course, is the wiring/grounding that you mentioned - logic dictates that something is amiss with the customer's power. Any way you (or an electrician) can check to see if there is a floating ground, hot/neutral reversal, over/under voltage, etc.? Can the customer try the machine using another outlet, or even better another outlet on a different circuit?

You never know: make sure any voltage switches (usually 115/230) and/or PSU on/off switches aren't hanging or sticking - stranger things have happened...

Non-electrical: is there any difference at all in any peripheral devices that the customer might be plugging in that vary from your local equipment (mouse, keyboard, monitor, printer, etc. - especially USB)? And when you say "he can't get it to boot" does anything happen at all - beeps, fans, anything?

 

did you get a response/fix for this?
I have a very similar issue...my computer works in the house but not in the office (separate building on it's own breaker) I even had an electrician wire a stand alone plug for the computer...it worked for a while , but then quit, computer won't boot past the usb mass storage devices. Boots fine in the house.

 

An unlikely suggestion - maybe the mains voltage in two different places are outside the levels the computer or it's PSU will accept (maybe the nominal input voltages for the PSU are slightly off too ?)

Dumb_Question
3.June.2013
Compaq Presario S5160UK DT261A under XP/SP3
Processor - Celeron 2.7 GHz
Motherboard - MSI MS-6577 v2.1
RAM - 1GB + 512MB (1GB +1GB max) DDR PC2700
PSU - Octigen 300W model 10270PSOTG ('upgraded' from original Bestec 250W PSU [in 2011?])
Nvidia GeForce 6200 graphics card in AGP slot.

 

A few more possibilities:

* Is the friend using a UPS battery backup? There are a few newer PSUs and PCs that require a Pure Sine Wave AC output - if it's simulated sine wave, the PSU won't turn on. Try bypassing any UPS or surge protection temporarily by plugging directly into a wall outlet and see if it boots.

* Does the friend have any USB storage devices (flash or ext. HDD) attached to the PC? Depending on the BIOS settings, the PC may try to boot to these first, causing the PC to freeze at or immediately after the BIOS startup screen. Unhook all such devices before attempting to reboot at your friend's house. Also remove any SD/Memory Stick cards from the card reader if applicable.

* If you have a multimeter, check the AC output of the power outlet. In the US, it should be between 110 and 130 volts.

Hope this helps.