Bad capacitors were the bad boys , i have replaced the starting capacitor valued 1000uF 10v just across the switching IC and it worked
That's good, however I usually do Not recommend to folks to work on their Power Supply. Cap's hold voltage a LONG time....Yes, they could properly discharge the cap's, but I look towards their safety. (One's that filter the incoming voltage are usually 100 volts...)
Regards,
joecoolvette
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Dell Support > Optiplex 960 > Manuals & Documentation tab > Service Manual (6460KB),
http://www.dell.com/support/troubleshooting/us/en/19/Product/optiplex-960
A) "Light Pattern,
Number 3 - Blinking Amber -
A possible motherboard failure has occurred"
This you must have known........however going on.........
"Number 1 and 3 blinking amber -
A possible motherboard, Power Supply, or peripheral failure has occurred"
The first thing to check with desktop computer failure, is the Power Supply.
If we are to agree that using the motherboard diagnostic LED's, and specifically the No.3 LED was blinking Amber; then we can agree it was motherboard failure in the first place.
However, me? I'm a skeptical computer geek.
I ALWAYS, test the Power Supply's 3 main voltage power rails FIRST, then I may go on to assume diagnoses has led to the motherboard, peripherals, etc.
From there, it's check the Radial Aluminum Electrolytic Capacitors on the motherboard, for visual capacitor failure.
The motherboard chipset going out, is a Rarity.
IF, it does fail; it's usually the Northbridge chip of the motherboard chipset; because it get's the hottest.
(That's why it has an aluminum finned Heatsink on it. Sometimes Southbridge chips do too)
Southbridge chip is next in line.
You don't know how many desktop computers, I have fixed over the years; that the problem was the Power Supply, and not the motherboard, as assumed by the owner.
Also it's all over the internet.
LED's light up, and fans spin; and people assume the Power Supply is OK.
This = No.
1) If ALL of the LED's were lit up at once, they would use less than 1 Watt of power.
2) EACH fan uses 2 to 3 Watts of power.
3) A typical Processor (CPU) uses 51 to 130 Watts of power.
Just depends on what Processor it is.
Therefore a Power Supply with a weak voltage power rail, will have PLENTY of power to operate those simpy little Light Emitting Diodes, and maybe spin fans; but will NOT have enough power to turn the Processor on.
Either test the 3 main voltage power rails, with a multimeter set to DC Voltage, (3.3 Volts, 5 Volts, and 12 Volts),
OR,
Use a KNOWN to be good, Compatible power supply; for a temporary test unit.
http://en.wikipedia.org/wiki/Computer_power_supply#Wiring_diagrams
http://www.playtool.com/pages/psuconnectors/connectors.html
Power Supply deemed to be good? Go on with the diagnoses.
Visually inspect the capacitors on the motherboard,
http://capacitorlab.com/visible-failures/index.htm
http://www.youtube.com/watch?v=Lut7MX5Dd_A
What? Are you cra-zy Joe? Did you not read I replaced the motherboard?
Ahem,
That motherboard you have, IF a direct replacement; is an NOS.
New/Old Stock.
Been sitting on a shelf for years.
Point?
Electrolytic Capacitors break down over time. It's the 'nature of the beast'.
They have Electrolytic Paste inside, which is a chemical.
It's known to break down over time.
Computer engineers know this, and use capacitors that are rated at TWICE what is needed. 200 percent.
So..........when the capacitor breaks down to 50 percent good, it is still 100 percent good for the application.
Point?
New purchase, or not IMHO it could be a bad motherboard.
Another point of interest; Electrolytic Capacitors do NOT always show outside visual signs of failure.
The Electrolytic Paste inside can just dry up, instead of developing a gas, (Hydrogen Gas), and not break the seals of the capacitor.
However, I would make sure the power is good, then disconnect all internal peripherals.
Peripherals are also the Harddrive, as well as the optical drive (CD/DVD drive), and Card Reader or Floppy drive.
(Outside peripherals; Keyboard, Mouse, Monitor, Printer, etc.
Leave Keyboard, Mouse, and Monitor of course; but disconnect any other outside peripheral)
That means disconnect the data cable from Harddrive to motherboard, and power cable to Harddrive.
Also same for optical drive/s.
Disconnect, the two cables from the USB header on the motherboard, for the Card Reader. (media)
Floppy Disk Drive data cable, and power cable, IF used.
LEAVE the front computer case fan connected, as it's cooling for the Processor. Ram Memory is installed also.
(NO graphics card if you have installed one. Connect monitor cable back to the motherboard. {Back of computer > I/O area)
So essentially we are talking just Processor, processor fan, and Ram Memory.
Turn the computer on.
Try to pull the BIOS Setup screen, up.
If no, you have a bad motherboard.
Now remember, this is AFTER the Power Supply has been deemed good.
BIOS Setup screen comes up?
Then reconnect the harddrive.
Good to go?
Then reconnect the optical drive. If drives, connect one at a time.
Check.
Then connect the second optical drive.
Good to go?
Then reconnect the card reader.
Had a post from someone on here not long ago; that we went through diagnosing; until he found out the Card Reader was the problem.
If memory serves it was one of the cables, coming from the card reader.
I'm guessing he ran a continuity test on the cable, with a multimeter set to OHM's, to check whether it was indeed the cable; or the USB header on the motherboard it plugged into.
He never stated.
Arranging all that prattle I stated above.......I mean Summation:
1) Test Power Supply voltage power rails, or use KNOWN to be good, Compatible power supply
2) Visually inspect Capacitors on motherboard.
3) Processor, processor fan, Ram Memory, ONLY; see if you can get BIOS Setup screen to come up.
For additional questions please post in a Comment.
Regards,
joecoolvette
SOURCE: pover up trouble
sounds like something is drawing down on your 12 volt supply drives or on board regulators. Try it without the drives connectged, and see if you can get the system to boot up(you'll just get a notice that your drives are unavailable, but you'll already know that, right?
got backup for your Dell?
SOURCE: Dell 5100 won't start... Power button blinks yellow.
hi disconnect pc and try to charge ups without anything connected
SOURCE: Dell Optiplex GX150 will not boot - no beeps but has error lights
You first need to make sure your memory is secure.
SOURCE: want turn on getting number 1 and 3 flashing
Your Power Supply has gone bad mate... known problem. You need to swap out the old power supply with a new one or maybe a working one (if you have another system)... the procedure is fairly clearly documented on the Dell Site n no Tags needed for that... :-)
SOURCE: Dell optiplex 330 flashing orange on the power botton
Try to clean the RAM and place it again in the motherboard.
For the Optiplex 320, a flashing amber light with no sound indication can mean 3 things.
1) Your power supply has failed
2) Your motherboard failed, most likely from a bad capacitor.
3) The front panel board (where the power button is located) is faulty or not connected properly.
I've worked with 10's of 1000's of Dell Optiplex's over the past 8 years and the flashing amber light is well known as a tell-tail sign of one of those three failure. Always start your trouble shoot with a PSU tester, then inspect the motherboard for domed or split/leaking capacitors...then on to the front panel which would require another panel and ribbon from the same model.
Test your PSU or replace it if your power supply units fan is not working your PSU is faulty
One bad lead can cause a computer to continue on a cycle or to shutdown or fail to detect/ boot up a computer hard drive
Test all leads that attach to your hard drive including electrical extensions,IDE,SATA
the leads from your MOTHERBOARD TO YOUR HARD DRIVE make sure they have a secure connection and are not faulty or just replace them they could be faulty
make sure all leads that are attached to your drives dvd\cd 3 1/2 inch floppy have secure connections and are not faulty even the electrical extensions or just replace them they could be faulty a computer needs its connections to continue its cycle and have an end so any faulty leads will end up with a computer error
even something as small as a faulty electrical extension or fan lead can cause you problems
computers need all of the data and electrical current to travel through every working device and to have an end to be able work properly
motherboard and a hard drive any leads between them will fail before your motherboard or your hard drive if its a flat ribbon 40 pin type IDE replace it this will be the first to fail
check all electrical power input and extensions make sure they are securely seated even the cd/dvd floppy drives need to have current go through make sure these drives are working
also check the Cmos battery and computer RAM modules make sure they are securely seated with no dust built up or in the sockets on some motherboards cmos batteries are soldered in
check you CPU make sure its securely seated and has thermal grease
hope it helps
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the power supply is good. i used the on board diagnostic to check it
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