Dell Optiplex SX260 Computer Won't Boot Up
 

SNIP
Inspect the capacitors.

Apparently there were some bad Nichicons, which would normally be
a good brand of capacitor. Most of the time, it's other (fly-by-night)
brands that fail prematurely. Nichicon is what you use when you need
a replacement.

http://en.community.dell.com/support.../18200664.aspx

Paul

Hi Paul,

I looked at every electroylitic capacitor for a bulge (even slight) and
I did not see one. Note: I once had this, no boot up problem, with my
NEC desktop computer and found some bad caps (bulged). After
replacing them, all was "well" again.

I did not measure or check ESR of any caps yet.

Thanks for your tip, John

Dell Optiplex SX260 Computer Won't Boot Up
 

wrote:
SNIP
Inspect the capacitors.

Apparently there were some bad Nichicons, which would normally be
a good brand of capacitor. Most of the time, it's other (fly-by-night)
brands that fail prematurely. Nichicon is what you use when you need
a replacement.

http://en.community.dell.com/support.../18200664.aspx

Paul

Hi Paul,

I looked at every electroylitic capacitor for a bulge (even slight) and
I did not see one. Note: I once had this, no boot up problem, with my
NEC desktop computer and found some bad caps (bulged). After
replacing them, all was "well" again.

I did not measure or check ESR of any caps yet.

Thanks for your tip, John


You can disconnect some stuff (storage devices), try removing
the RAM modules, and listen for an error beep pattern. Or, if
the computer has the Dell four-LED diagnostic output, you could
look for that. My purpose in doing such a test, is to see if the
processor is able to read BIOS code or not, and beep when
it cannot detect the presence of any RAM.

If it doesn't pass this test, check that the ATX12V and
main power cables are fully seated.

A computer will not run, if the reset switch on the front
panel is crushed in the "ON" position. The reset is momentary
contact, and a failure there could give a non-starting symptom.
The PSU fan would run, but nothing else would happen. Disconnect
the reset wire pair, and see if symptoms change.

Paul