I have a 4 yr old Optiplex 775 Desktop that won't boot. Hard drive spins, but no Post Beep, nothing form BIOS on the monitor. All the fans spin, MOBO power indicator lights up. LAN and HDD indicators on front panel are lit but no boot. Was fine yesterday and stone dead today.
Already tried resetting CMOS battery, booting with no RAM, Booting with HDD unplugged, ...No error beeps. Reseated the SATA connectors, power connectors and front panel to MOBO connector. Nothing.
Starts to power up and just fails . Hit the power button again and it shuts down immediately.
Anything at all anyone can suggest to even try to get rolling again?
Thanks in advance
Failed power supply...?
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The best thing to do at this point is to be methodical - the likelihood is that either the power supply or motherboard has failed but there's a few things that we can do to narrow down the failing component. Also, can I double-check that this system is either an Optiplex 745 or 755? The reason I ask is that there was no model released with the model number 775.
Some of these you may have already tried but I'll include everything for completeness:
** Some of these steps call for removing components, please make sure that you remove the AC power cord from the back of the system before doing so and also take anti-static protection measures - if you need any assistance on how to remove components, please find your manual at http://support.dell.com/manuals **
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Thanks for the reply.
First, it is a Optiplex 755 . I apologize for the typo.
I followed the steps you detailed. Here are my results:
1) Solid Green on Power button
2) Diagnostics 2 & 4 lit ( Also Lan indicator, if that is significant)
3 & 4 ) Power Button Solid Green but only diagnostics 1 lit ( and still Lan )Two long beeps at boot up
5) No flash or display on monitor at all. Total of 7 tones, varying duration and interval.
6) Known Good ( but used) PSU.. only had one SATA power so was only able to power MOBO, HDD and FDD (not optical drive) No change.
Thanks for all the help
Ram is Bad or Incompatible. Try 1 stick only.
A possible graphics card failure has occurred.
Memory modules are detected, but a memory failure has occurred.
Report Unresolved Customer Service Issues here: Dell - Unresolved Customer Service IssuesI do not work for Dell. I too am a user. The forum is primarily user to user, with Dell employees moderating.
System has 2 x 1GB sticks of Ram. I have tried with both removed and adding each back separately, and in different slots with each. No change. So unless both sticks went bad simultaneously and spontaneously, I amd skeptical that this is my issue. I will see if I have another known good stick I can try, however.
The diagnostics LEDs 2 and 4 indicate that there is an issue with the video subsystem - either a problem with a video card installed in the system or if your Optiplex is using integrated video then a potential problem with the motherboard. I've sent you a friend request - if you can accept and send me your service tag in a private message, that'd be excellent.
The system appeared to be behaving correctly when all components were removed - it's normal to get the diagnostic LED 1 showing as this indicates no memory installed. The LAN link lights are a good indicator that power appears to be working okay.
It's a shame that you didn't manage to catch the beep codes correctly but I suspect that at step 5, these were just indicating that there was no memory installed. Can you try step 5 again but making sure that memory is installed? If you hear beep codes, these will come in a series of three separate beep groups - so you'll get a couple of beeps then a pause, then some more beeps then a pause and finally some more beeps. If you can count the beeps in that fashion, for example 1 beep, pause, 3 beeps, pause, 1 beep - that would be a great help.
At the moment, I'm leaning towards a motherboard problem but the more information we can get on this, the better.
Hi John, sorry for the delay . just to clarify so i can re-test step #5 .
-I/O Cable diconnected
- HDD and FDD...Unplugged or connected?
-Optical drive Unplugged or connected?
No amount of plugging or re seating bad ram will make it good.
You must start with at least 1 stick of known good ram.
The most common error I see is users demanding that ECC, Buffered, Registered TOO SLOW ram work.
Memory Type: DDR2 PC2-8500 (non-ECC)
No Speed, I know that. This is the original RAM that came spec'd with the machine so I know it's compatible.
And I know that reseating ram won't make it good, but I have trouble believing that two separate stick of RAM both croaked at the same time. Possible, but the odds are long. So by removing them and re-installing then one at a time, I should have been able to at least see if one of them had gone bad. I will see if I have any known good compatible RAM to try though, just to eliminate that remote possibility of simultaneous failure of both sticks
Repeated test 5 - RAM in- I/o cable unplugged, CMOS battery removed. No beeps at all. No flash on screen.
tested with HHD, FDD and optical drive both connected and disconnected. No error beeps.
No flash of video
Also tested with a simple PCI video card, No video output at all
Power Surge, static damage, lots of things could make ram go bad. What you haven't said is that you tested the ram in a known working system. If you don't have that then you need to spend the $50 to $90 for a good known compatible sticks of ram.
Specs: DDR2 PC2-8500 • CL=7 • Unbuffered • NON-ECC • DDR2-1066 • 1.8V • 256Meg x 64 •
If it's at all possible, can you try the memory from your faulty system in a known working system? Or if you have known working memory, please try this in the faulty system. This would tell us for sure if the problem is the memory.
If I was your technical support agent on the phone and your system was in warranty, I would replace motherboard and memory to get this fixed first time. Because of the age of the system, I'm presuming you're out of warranty so it would be worthwhile trying to get known working memory first if you can beg or borrow this!
OK, tried a memory swap from a known working Optiplex 755. Identical 2X 1GB Samsung sticks.
Problem persists with original computer.
Known good RAM has no effect on suspect computer.
RAM from suspect computer works fine in known good machine and registers full 2GB ( 1.96)
So not the RAM.
So looking at MOBO? Will dell stock parts for that still ? And yes, you are correct, we are out of warranty, so it will be a purchase if I can get the part.
Thanks for the continuing help, look forward to your responses
Look here, here, here and here.
Obviously, you need a mobo with the right form factor (eg, tower, small form factor, etc) and be sure to ask if new, used, refurbished and about warranty.
Dell may stock these motherboards but it depends on where you are based. The best course of action would be to call your local Dell Technical Support team as they will be able to quote you for the motherboard (presuming, of course, that it's stocked in your region).