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Is this PSU dead?

Last response: in Components
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May 25, 2008 1:33:29 AM

I got my son a new case CM690 he was having heat issues in the old case. Well I put everything in the new case and it wouldn't start up right. Fans would come on but no boot. I would have to restart it a couple of times to have it post. It sounded like it was surging the fans would change speed. Well now the light on the motherboard comes on but nothing else. No fans at all. Any ideas? This system is about 2-3 years old.

Thanks
Kelli

A8N- SLI ASUS
AMD 64 3200+
4gig ram
XFX 7600GT
Ultra 500W psu
windows xp

More about : psu dead

May 25, 2008 1:56:53 AM

If the system worked until the new case the first thing I would look for is if you placed all the standoffs correctly and if anything might be shorting out.
May 25, 2008 1:40:54 PM

I have checked the standoffs and they look fine. I am not sure about the case front panel connectors on the motherboard they might not be right. I moved them and still nothing but the green MB light. Any ideas?
Kelli
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May 25, 2008 3:05:06 PM

The psu has all silver wires so I cant tell which is green. It is a ultra fx500

Thanks
Kelli
May 25, 2008 3:56:08 PM

Thanks, I did the jump procedure and nothing! I will try another PSU. How can I get one that will be sufficient to run two 7600gt's in SLI

Kelli
a c 144 ) Power supply
May 25, 2008 4:51:07 PM

kelcorn said:
The psu has all silver wires so I cant tell which is green. It is a ultra fx500

Thanks
Kelli


Practically every PSU I have seen uses a standard color coding for all the wires. You have one of the few that doesn't. So we have to do this the hard way - well, harder than simply looking for the green wire.

Hold the main PSU connector (the big 24 pin one) so that the plastic tab that locks the connector to the motherboard is on top. Counting from left to right, the lower row is pins 1 through 12. The upper row is pins 13 to 24. What should be the green wire is pin 16. That will be the 4th pin, counting from the left on the top row. The wires on either side pins 15 and 17) are ground pins. Your motherboard manual also should tell you which pins do what. Pin 16 should be called something like PS_ON.

I took a quick look at the link. Pin 16 is a control line. It will have very little voltage on it. When you ground it, all it does is send a wakeup signal to the PSU.

ausch30 is right. If the PSU fan doesn't spin, your PSU may be gone. However, the converse is not true. A spinning CPU fan does not mean that the PSU is good. You could have a problem with the 3.3 volt or 5 volt outputs. Unfortunately, the motherboard LED doesn't mean much either. It's powered by a small (about 10 watts max) 5 volt power supply that is completely separate from the main power supply.

System troubleshooting:
The system worked before you put it in the new case so something probably isn't assembled properly. It's possible, but not likely, that some component failed while you were changing cases. Doublecheck all the wiring. If you cannot find your motherboard manual, you should be able to download a copy from the Asus website.

Did you remember to connect the CPU power plug - that's probably a small 2X2 plug that connects somewhere around the CPU socket. I saw a bad case power switch once in a case I was recycling. The simplest way to check that is to swap the power switch with the reset switch. The case LED's do not matter right now.

After that, try this:
http://www.tomswiki.com/page/Troubleshooting+a+New+Buil...

Consider your system to be a new build. After all, you put PC parts into a new case. It's kind of long, and because I recommend that you completely disassemble the system, it's a fair amount of work. If you decide to go this route, I suggest that you leave the CPU and HSF on the motherboard. Disassemble everything else, including pulling the RAM. In the first few steps, you will not need the monitor, keyboard, and mouse.

A system will successfully POST (single short beep) with only PSU, motherboard, CPU and HSF, RAM and a video card. You do have a small speaker plugged into the motherboard?

John Casteel





May 25, 2008 8:16:08 PM

Ok don't laugh to hard. I had the front panel power button wired to the MB wrong. I have power but I still have problems. I will do a search. For SLI setup.

Thanks
Kelli
a c 144 ) Power supply
May 26, 2008 1:48:06 AM

Not too surprised. After all, the system DID work before.
!