Desktop won't boot-blinking power & h/d led

geno368 · Oct 6, 2008, 10:46 AM

My sister has a Dell Dimension 5100 w/XP Prof., 1MB Ram, Pent 4 @ 3.2 ghz. All of a sudden it won't boot. When you plug in the power, the power switch led blinks orange in unison with the h/d green led.
This is what I have tried:
I pulled the power supply 24p connector and shorted the black wire to the green wire and the fan then came on..so I figure p/s is ok?????
I then removed the modem card and the video card as well as the memory and all drive connectors. Still same response. What do I need to check? Motherboard bad?? Thanks

H3X4D3C1M4L · Oct 7, 2008, 11:22 AM

It might be the motherboard, but shorting out the ATX_ON pin on the PSU and getting the fan to spin is hardly a comprehensive PSU test

You might try to find another PSU that works to test and see if its the motherboard, but it'd have to be a Dell PSU (Dell's PSU's are proprietary I believe, at least on older models)

swimtech · Oct 10, 2008, 02:20 PM

Look for swollen (bulging tops - sometimes with orange/brown material coming out...) capacitors on the mainboard around the CPU socket and next to the memory modules - if so you've found your problem.

About the PSU - and this would take a bit of work... I know for sure that the PSU's of the Optiplex GX260, 270, and 280 units are not proprietary - a standard ATX power supply can be substituted without frying anything. A check of Dell's site for the part number for a replacement PSU for your Dimension 5100 might match the part number for one of those machines. If so, you can swap in a known good ATX supply without fear of damage.

geno368 · Nov 3, 2008, 11:17 AM

I have finally traced the problem to a damaged X8543 front panel on this system if anyone has one for sale. I also need to know if the damaged USB port on this panel could cause the blinking amber light and no boot. I have replaced the PSU already. If the port is shorted to ground, would it damage the MB?

GigaWatt · Nov 4, 2008, 08:47 AM

which port and which pins is a more important question...

geno368 · Nov 7, 2008, 10:41 AM

Solved.....I finally found a front i/o panel assembly and replaced the shorted one. I replaced the cmos battery I had pulled and...it's back to normal....Thanks for all the help