GX280 Issues - capacitors look ok though

[roger8wilco]

I got a GX280 off ebay a year or so ago.. From the symptoms, it sounded liks a PSU replacement but when I got it, it wasnt the problem.

When I try to turn on, it goes on for a few seconds, fan a full power, and then shuts off for a few seconds. Then it repeats it over and over. Sometimes it'll stop repeating and turn on, not POST, and just stay with on with the fan at full power. Typically after this happens and I turn it off, it will actually boot up.
I havent had it recently happen, but it has been known to shut off randomly (usually when its idle like overnight when not in use).

I took a look inside and see no bad capacitors, no bulging, leaking, etc. A number of caps are RubyCons (i think, but pretty sure) so I think they may have been replaced, at least 5-8 of them..

Another note, related or not, it wont take more RAM... if i put more in, I get bad memory beeps when it boots up.

Any ideas? Does it sound like it could be the caps?

[Solder Boy]

Re: GX280 Issues - capacitors look ok though

You will need an ESR meter to determine which are the bad caps on the motherboard if you can't see any obvious ones that are bulged. I'd also check the voltage on the CMOS battery, if it's below 2.9 volts replace it.

As far as the RAM issue goes, check the RAM using Memtest86, it might be bad.

From what you have described, it does sound like a bad cap problem especially since you say it does POST.

Good luck!

[PCBONEZ]

Re: GX280 Issues - capacitors look ok though

Some GX280 got defective Nichicon HN or HM series caps.
Date codes (on the caps) will be between 2001 and 2004.
H0133 would be week 33 in 2001
H0433 would be week 33 in 2004
[I have no idea what the 'H' is. Sometimes it's another letter.]

Other GX280 (especially the Small Form Factors) suffer from heat issues due to too little airflow and that will even kill good caps eventually.

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