What could the problem be?

My friend's computer recently seem to have fried... He turned on the computer, and then suddenly there was some static sound in his computer and it shut off by itself; it then refused to start back up at all. We both talked about the possibilities of what could be wrong, and we came to the conclusion that it could possibly be the power supply. So, he took the power supply out of his brother's computer and stuck it onto his own and the computer started up perfectly fine. We decided that it must be the power supply that's causing the problem.

So! He went to a nearby computer store to pick up a power supply. The store is one of those small side-stores owned by some asian (nothing against asians here, I'm asian as well. I'm just saying this so you guys know it's not some large store or something) guy. My friend asks for a power supply with at least 400W, and the guy gave him a power supply that was supposedly "450W" or so, and sold it to my friend for $40 CAD (VERY inexpensive).

My friend got back home, plugged the power supply into his computer, and started it up. It started up fine, but when it got to the Windows screen (before the log-in), the computer would automatically restart itself. It would then keep looping itself over and over again at that part, never being able to fully start up. Could the problem STILL be the power supply, or could it possibly be some other problem that's causing his computer to malfunction? Keep in mind that he HAS had successful results by sticking in his brother's power supply, so might the one that he bought actually be some bad power supply that didn't have enough power to start up his computer fully? Or would it be some other problem in the computer that neither he nor I have thought of? Thanks for any help in advance.

 

See how it goes with this>

To start your computer by using the Last Known Good Configuration feature, follow these steps:
1. Start your computer.
2. When you see the "Please select the operating system to start" message, press the F8 key.
3. When the Windows Advanced Options menu appears, use the ARROW keys to select Last Known Good Configuration (your most recent settings that worked), and then press ENTER.
4. If you are running other operating systems on your computer, use the ARROW keys to select Microsoft Windows XP, and then press ENTER.

If that doesn't get him in there must be another issue. Possibly that PSU.

 

Yes, it does stay up. His brother needs that power supply though, therefore it cannot be a permanent solution.

As for #2's suggestion... he just told me that he returned the power supply and he's going to get a different one, from a store that has more credibility. I'll let everyone know how that works when he's got it in his computer. Also, if anyone has any other ideas of what the problem could be, let me know so he can try more things. Thanks!

 

Bump. Please keep the suggestions coming.

 

Tell your friend to buy a reputable brand like Antec, ThermalTake, Zalman etc.

Cheap "no-name" power supplies are trouble.


The number of Watts isn't as important as the number of amps, and the quality.

 

"Last Known Good Configuration" only works for XP. You didn't list your OS...

What is your Windows version? (95,98,98SE,NT,2K,ME,XP)

A loop can suggest a needs to fix the bootup file in a couple OSes, or if it works fine with his bros power supply, give the 450W to his bro...