[Aviator19]

I think I have a bad Power supply Unit (PSU).

Computer specifications below.

Symptoms include:
Unpredictable instant uncommanded computer shut downs

Background:
I bought this computer system a year ago. After the first few months I noticed the computer shutting down every once in a while, no warning. As time passed these started happening more frequently. I haven't really thought anything of it until the last 3 months when I started thinking it's more serious. I don't thing its the new Windows 64 bit OS doing it anymore. I also noticed the computer started shutting down more frequently when intense programs where loaded (such as Flight simulators, the main job of this computer lol, other programs - games - like BF2).

Load a program now = instant shut down.

Just letting the computer run (Windows loaded) = maybee half an hour of web browsing, etc.

At present I can barely keep the computer on long enough to do anything.

Visual inspection of the PSU (Xion LC-B450E):
4* 1000 microfarad capacitors appear convexed at the top (bulging).
1 resister, looks like a 10 ohm R, Looks like it has been overheated. Colour bands are almoast unreadable. Will have to verify it's resistance after extraction, if it has any left, lol.

I have basic electronics knowlege and some experience in componant extraction and replacement.

I'm not all that experienced though so here's the question:

If indeed the problems are said componants, is it really that easy to epair a PSU? Why do they costs so much!?
A little reasurence would help, lol. I am out of money so I can only try this once. Advice would also help if there might be something I overlooked. I haven't been able to find a schematic for any PSUs so I will have to schetch my own after I open it up again. So I don't know where in the circuit those Cs and that R are.

Also, would it be possible to increase the output of the PSU or would I have to make too many changes inside? Not an electronics expert yet. I can't buy a new PSU either for a while so this has to last. I admit I overlooked the PSU when I bought this machine! I bought everything from the same shop so I was sort of expecting them to not under-power me. My mistake!

Thanks for any advice/help that can be provided.

Computer:
Xion LC-B450E Power supply unit (specs below)
MSI7125 1B0
AMD Athalon 64 3500+
2*1GB DDR400 RAM from Crucial
Radeon X700 256MB PCI-e

Some other things are irrelavent as I have to unplug them if I want the computer to run:

Hard drives, right now I have 2 plugged in.
2*500GB Seagate SATA II
1 400GB Hitachi SATA I (unplugged)
1 CD/RW drive
1 DVD ROM drive (unplugged)
1 1.44MB floppy (unplugged)
CPU fan Thermaltake
Blower Thermaltake fan
All other fans unplugged since it's winter (computer came with 3)

Temperatures:
We have no air conditioning so, during the summer the average CPU temperatures where 55ºC. Case temp was averaged around 40ºC. This is when I thought it was an overheating problem.

Winter temperatures now put the CPU average temperature to 38 to 40ºC. Case temperature same.

PSU
DC OUT:
+3.3V 28A 92.4W
+5V 50A 250W
+12V 18A 216W
-5V 0.8A -4W
-12V 1A -12W
5VSB 2.5A 12.5W
+5V +3.3V + 12V MAX COMBINED=422W

According to my calculations, if everthing there was maxed out, it would equal 566.9W
I also included the watts beside each amp (not included on PSU's label) using the fourmula Volts * Amps = Watts.
Do I see some inconsistancies just by reading the label? lol

 

[blackduck30]

I am no electronics expert either but the only advice i can offer is that generic type power supplies similar to yours are the reason we have written a power supply guide.
There is a chance you could replace the faulty components with some better quality units but my worry would be that you are only moving the weakest link somewere else. There may be other components that are on the verge of failure. That power supply is really not a quality unit I would consider spending money on.
I understand the shortage of cash but i'm also concerned you may just be wasting your money trying to resurect the old unit

It is not a repair guide but it may help understand why we recommend the power supplies we do in the article so if you have the time I suggest having a read of this article our team put together
http://www.techsupportforum.com/f70/outdated-power-supply-information-and-selection-107466.html

EDIT: I just done a quick google on your power supply and it was not a good outcome. I suggest you also google it and see if you still want to repair it, you really need a quality 550W + unit

 

[dai]

pcie requires a min of 24a on the 12v line yours only has 18a so it is time for an upgrade even if it was working