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Computer won't power up after disconnecting power supply

By bgstewar ยท 20 replies
May 4, 2006
  1. My first post...

    I received my new DVD DL +/-RW drive today and eagerly installed it. I of course unplugged my computer's power supply while doing it. After plugging the power back in, the green LED on the back of the CPU started blinking (never noticed this before), and when I hit the power button, NOTHING happen. No fan turns, no lights, nothing. When I unplug the power supply, the green LED blinking gets slower and slower, and after about 15 minutes it totally stops. I plug the power suppply back in and it starts blinking all over again and still the power won't turn on.

    All I did was replace a CD-ROM drive with a DVD Multi drive. I didn't mess with anything else, so there should be no power supply shortage or problem. Any thoughts as to what could be happening?

    By the way, I have a 2 year old Compaq computer with 2.0 ghz Athlon 64, 1 gig RAM, no problems thus far.
  2. mailpup

    mailpup TS Special Forces Posts: 7,322   +591

    While installing the new optical drive, you might have inadvertently loosened one or more connectors. Recheck all data and power cables to make sure they are tight, including all those to the motherboard.
  3. Mkoll

    Mkoll TS Rookie

    On my first computer I ever had I thought I knew everything so I disassemble it and put it back together. Goes great except I had put an extra cord from the PSU into the cd drive. I had shoved it in so when I turned on the computer it would just shut down. Check your PSU cables!

    Yeah my cd drive was dead after that.
  4. bgstewar

    bgstewar TS Rookie Topic Starter

    I made sure all connections are tight, which they are. I opened up the case and it is my motherboard that's blinking a steady green light. When I unplug the power, it diminishes, which I read is from the battery supply to the motherboard. Anyway, what else could this be? What could I have done by installing a DVD drive that blew my motherboard up?
  5. mailpup

    mailpup TS Special Forces Posts: 7,322   +591

    Maybe you were ungrounded and gave it a shot of static electricity. The diminishing light is a result of a capacitor(s) discharging. The only battery is the CMOS battery and it doesn't operate like a car battery. That is, it doesn't charge up when the PC is plugged in and it doesn't run the computer when PC is unplugged.
  6. bgstewar

    bgstewar TS Rookie Topic Starter

    So am I SOL? Is it the mobo? Anything I can do?
  7. mailpup

    mailpup TS Special Forces Posts: 7,322   +591

    By any chance does your power supply have a on/off rocker switch on the back? Is it on? I don't mean a red voltage adjustment switch, however. If that isn't it, do you have access to another power supply to install and test? As unlikely and coincidental as it might seem, perhaps the power supply has chosen this moment to die.
  8. bgstewar

    bgstewar TS Rookie Topic Starter

    Well, when I unplug the master power supply to the mobo and plug the CPU back in, the green light turns on and stays on as if everything's normal. When I unplug it to plug the mobo back in and then plug it all back in, the flashing begins again. Could this be a power supply issue maybe, like you said? Is it possible to install a new drive and actually blow your power supply completely? I would think if I didn't have enough power, it just wouldn't power up. But even when I unplug everything except the hard drive and video support, it still doesn't power up.
  9. Samstoned

    Samstoned TechSpot Paladin Posts: 1,009

    when I unplug the master power supply to the mobo and plug the CPU back in,
    if cpu is processor ,you should not be playing with this and the PSU.
    if you plugged the processor in while the MB was hot you may have blown it out
    if you turned the psu on and then plugged it into the motherboard you could have blown the MB.
    this is a learning curve lots of people go through when learning system building
    or go to school and blow up there machines
  10. bgstewar

    bgstewar TS Rookie Topic Starter

    It was the PSU!! I bought a new, more powerful one, and voila!! Perfect!!
  11. paranoid guy

    paranoid guy TS Rookie Posts: 408

    What a subject! Did no-one else cop this or am I the only one that found this funny? I know that's not literally what you meant, but imagine it was... :haha: Anyway glad to hear you got it sorted. There are a lot of problems here that seem to be psu related, and unfortunately the usual answer is to get a more powerful one. I can forsee 600w psu's becoming standard...
  12. Tedster

    Tedster Techspot old timer..... Posts: 5,746   +14

    funny..... my bvtt's still stinky after I don't wipe!
  13. joshuamays

    joshuamays TS Booster Posts: 137

    LMAO sad but true...
  14. Curtis3820

    Curtis3820 TS Rookie

    Power Supply blinking.

    If you purchased a new Power Supply, you have wasted money. To fix this problem: Unplug the Power Supply from your Motherboard, then unplug the
    FRONT USB cable from the Motherboard, then plug-in the Power Supply to the
    Motherboard......the green light should be back to normal (on). Then, plug-in
    the front USB cable. This will fix your problem. For some reason, the Motherboard
    can't reset itself until you unplug everything from it. Hope this help.
  15. raybay

    raybay TS Evangelist Posts: 6,908   +10

    We have actually found this to be a fix without knowing it, as we have gone so far as to disassemble the computer looking for a reason for the failure... found nothing... reinstalled everything, then it worked..
  16. omgPatriceIsOn

    omgPatriceIsOn TS Rookie

    Thanks Curtis3820! I'm glad I read to the end of this thread. You saved me from spending money on a power supply. I followed your directions but played it safe and unplugged all the wires on the motherboard. I'm a former pc technician so I can put the wires back easily. One note to non-technicians, (this is going to sound stupid to tech savvy people), keep the power cord plugged into a live power source while following Curtis3820's instructions.
  17. PantzMaster

    PantzMaster TS Rookie

    I'm afraid to build a computer now.
  18. x128

    x128 TS Rookie

    late post

    I know that I'm late to the game, but just an FYI.

    While unplugging and reconnecting cables can sometimes fix power supply issues (usually because of discharging built up static) there are plenty of times where the power supply is simply going to be dead/malfunctioning. Power supplies are designed to take the brunt of any power-related surges, spikes, or voltage irregularities to protect the other components of your system.

    So, by all means, try unplugging cables first to see if that works, but don't be surprised to find that the supply is dead. It may have sacrificed itself so that your motherboard could live on. A good idea would be to purchase a battery backup unit (UPS) that would help protect your entire computer, power supply included.
  19. beth1964

    beth1964 TS Rookie

    I had a computer to do this today. I used a hot blow dryer on the back of the PSU for a couple of minutes and it booted right up.
  20. kimsland

    kimsland Ex-TechSpotter Posts: 13,810

  21. megabomination

    megabomination TS Booster Posts: 151

    Your guide is very helpfull kimsland.
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