Optiplex 755 won't boot

I am having an ongoing issue with a Dell Optiplex 755. It randomly shuts down - usually it seems to be connected with an update and after a day or two seems to settle down. This machine has recently been reassigned to handle a program that should run 24/7. So, in the past it was OK to wait out the quirks but now it needs to be ready to go all the time. I have run the Dell diagnostics - no errrors. I consulted with Dell chat (machine is still under warranty) and they suggested I update the BIOS. Ran the Bios flash the chat-er sent me via a link and updated from BIOS A09 to A17 and now it just power cycles - it seems to want to start but never does. The power light is solid amber and the numbers 1, 3 and 4 show up for a few seconds and then all goes black - then the cycle repeats. I let my Dell chat-er know the status via email and I have not heard anything from him (have I been ditched??) I have been researching this on and off for a couple of years (like I said - it would resolve itself so I was never under the gun to get it completely fixed) and have tried a number of things in that time period but now what it is doing is extreme and I really need the machine going. From what I am reading I think it may be a power source issue...can anyone walk me through what I need to do to 1)verify that it is the power source and 2) what steps I need to take to replace the power source if indeed it needs to be replaced? I am leaving work for the evening so I will check back in about 16 hours. Thanks! P.S. I am running Windows XP 32 bit.

 

Sounds more like a bad bios flash now...re-get the bios update directly from the site yourself making certain you absolutely have the correct most latest (even beta) version avail and reflash it on a non rainy day

Power supply: If the label is not easily visible, You may have to remove the power supply entirely to see the wattage...which is sometimes not listed or coded intothe model number like whammy550 etc...look for the label and see what the total out put power is in watts and/or a brand/model name to look up on the net.

To replace determine the best replacement power supply... First look at how it is connected to mobo and determine type....
at (two plugs in line with black to black), atx (one integrated plug- usually white plastic w/single hitch-clip) atx 12v (same as last but slightly larger) these power supplys usually have connectors for both at and atx 12v and usually have an additional 4 pin connector that plugs into the mobo seperately from main power (white plastic) connector, then theres sli and crossfire video cards..if multiple video cards will need multiple outs to them (on at or atx w/agp video... may use ide type power to each video card)
to figure what wattage you need there are configurators avail on the web (sorry no link) or just use the overkill method and get something huge and heavy...lol

drives...for if you have a floppy it needs to have a floppy connector...(most do)...if you have sata drives vs IDE then you need than many of the appropriate type connectors sata are thin..ide power are 4 pin and slightly D shaped squares

 

Hi rickmamo,

Thanks for your response. While the machine is not running I am going to check the power supply to see the wattage and other information as you suggested.

As for the BIOS flash - I have disconnected the machine from all power sources and I hope that it will boot when I reconnect and try powering it on - but in the event that the bad behavior continues - meaning it spins for a few seconds (like 5) and then the power cuts off - how would I reflash the BIOS? Also, this same behavior was exhibited one other time before the BIOS flash. Would this information change your mind about the bad BIOS flash and lend more weight to the possiblity it is a bad power supply?

Thanks again for your time and input!

 

>>it spins for a few seconds (like 5) and then the power cuts off

that sounds like the BIOS fan alarm feature that shuts off system to protect from overheating if the fan is not spinning at X rpms...check bios settings to disable any and all system health, HW monitoring, or alarm features....i had an asus mobo that did same thing untill i disabled fan alarm and then later i flashed bios to correct prob as well as upgraded to a high rpm fan for good measure

likely yer PS and BIOS are ok...i def think it's the BIOS setting now that you mention fan spinning for a few sec and then off...

 

alternately you could remove unecessary fans temporarily...just not the cpu fan or video card fans...case fans and such connected to the mobo especially...ones connected to the power supply out leads directly can prob be excluded...but not disregarded entirely

 

If the machine is still under warranty throw it back in Dell's lap to repair.

 

Hi - I've been out tending ill children so I apologize for the delay. To bring you up to speed...as per Dell chat suggestion I checked and reseated the memory and video cards and other mobo connections. The machine did start up after being totally disconnected from all power sources. Did not replace the power supply because I didn't have one available to swap. I also found reference to issues with Intel Managabiltiy Engine so I removed the Intel Mgmt Eng interface and Intel Mgmt Tech via Add/Remove Programs. When I left work on Wednesday the machine was up and running and has been running without incident since.

While the machine is running I have no idea if/when it will start acting up again. win2Kpro - I love your suggestion to throw it back at Dell - the problem is - that option is never presented to me...In the chat I was directed to pay attention to what numbers/lights come on during the power/boot process (the numbers 1,3&4 lit in orange as was the power button)...I was sent a lengthy list of things to try and at the end there was an offhand comment that if the lights were indeed orange it could indicate a power source issue. Any suggestions as to how to get Dell to replace?