Precision T7500 workstation powers up for only 3 seconds

The T7500 runs with the riser removed?  If that's the case, it sounds like you already troubleshooted it.  I don't know to what extent a riser can be troubleshooted or fixed other than to replace; but would have to leave it to one of our other experts or Rockstars.  You already tried re-seating items which is a good start.

May be this link will help?  https://www.dell.com/community/Desktops-General-Read-Only/T7500-Riser-Card-broken/td-p/5061742

This sounds strangely similar to a problem I had with my T5500. After trying unsuccessfully to install a 2nd X5670, it began exhibiting some strange behavior. It wouldn't power up at all. When first plugged in, it would briefly flicker to life then power off. Pressing the power button would do nothing. No lights, no beep, no video - nothing.

Then I cleared the CMOS. And it booted - once. I then went into the BIOS made a few changed and tried to shut it down. But the power button wouldn't shut off the machine, so I yanked the plug. But when I plugged it back in, nothing happened again. I reset the CMOS again, and it booted. But the same cycle repeated.

So what I did is went into the BIOS after yet another CMOS reset and under Power Management set it to automatically power up after power loss. The power switch still will not work properly, but as soon as I plug it in or turn on the power strip, the machine boots up.

TL;DR Try resetting CMOS and see if you can get into the BIOS. If you can, under Power Management see if you can set the machine to resume after AC power is restored.

A low CMOS battery can also cause all sorts of bizarre problems.  The T7500 is 10 yrs. old and the batteries last about 5.  Be sure to use lithium vs. alkaline.  It's a cheap fix and if it doesn't work, you still have a new battery on your MB(s).

Thanks for the reply.  The problem seems to have resolved with my reseating some memory, but that only lasted 1 day.  Since then I have removed the second CPU riser (and memory on that riser) and the problem seems to be OK for the last two weeks.  

Considering this, do you still think I should put in a new battery.  I remember repolacing it about a year or 2 ago.  Not sure if I used lith battery.

Up to you if you have a battery tester and want to test it.  It's a 3v battery.  It should show at least 2.7v.  Low 2's and it's time for replacement.

Or, if you want, replace it and you know it's ruled out.

It's also possible for peripherals to short or die out when they get older.  Glad you got your T7500 running again.

OK,  thanks.  I am making arrangments to get a battery tester.  But, although I have used PCs from the very first Dell, I lack the knolwedge to get the battery out.  In fact I have ruined at leas one motherboard in the past.  Is there a tooll that I could purchase that gets it out?  Thanks.

T7500 Service Manual

T7500 Tech Guide

Removing the battery is in the service manual.  As for a tool, I have a set of very small screwdrivers that could be considered jewelry screwdrivers.  A regular very small screwdriver is used to push the tab that releases the battery.

Thanks.  My manual had the text but no clear pictures like this.  I will try it this way.

You're welcome.:Smile:

Hello Brother! I'm facing the exact same problem, when I plug raiser out it works perfectly fine but when raiser is plugged in I turns on only for 3 seconds, have u find solution? I want it work with raiser...

Hi @MakesOwnWeather,

Though it's been over a year, did replacing the CMOS battery work?  We didn't get to hear from you since that suggestion.

I wrote a detailed reply to you, but could not post it.  email me at .  In the SUBJECT put in BOLD ALL CAPS:  "YOU WANT TO ANSWER ME ON DELL POST."  Reply here to let me kknow you sent the email.

I cannot answer you outside of this forum.  I'd suggest to use private messaging, but it hasn't been working well in Android since changes were made.

Sorry that somehow your post was dropped.  What a pain.  Can you retype your post?  May be type it in a word.doc first so it's saved, then copy & paste into the forum.  I'm hoping whatever your answer is, it will help other users.

Hi - I answered Joan, above, with a solution to your problem, but I do not see what I posted.