help! powersupply/HD troubles

hey i need a little help.
my powersupply died a little while ago and so i decided to replace it (ATX)
so i plugged everything into my asus CUBX motherboard and the PC powers up just fine if i plug it into my A: drive and my 2 cd rom drives, but when i plug in my HD the PC flicks on for a split second and then turns off and wont turn on again... i have no idea whats wrong with it.... any idea?

 

ok scratch booting up normally if the HD is not connected. The PC will turn on but there is no POST... so that means it might be the motherboard right?....any help appreciated.

 

trying to get a clear picture. Your computer should boot even without a hard drive to a certain point. it will check the memory and check for all of your devices. then it will go through a boot sequence of (a drive) then look to boot from the (hard drive). Even without the hard drive you should get to that point. But i think your saying that the computer never shows you any information on the screen at all when you plug the hard drive in. In that case, (assuming that without the hard drive plugged in you get as far as i said above), i would think there is something wrong with your wiring. Maybe, the wiring to, or from, or in, the hard drive is bad making signal for the motherboard to shut down before it even starts. just a guess.

 

ok i'll try to detail this a little better
my powersupply died on me about 3 days ago so i replaced it
1. when i plugged everything in and tried to start the PC it wouldnt start. the green LCD would flick on and then off immediately
2. so then i unplugged everything and tried it to see if it would power up. it does
3. so i start plugging things back in and then when i plug in the HDD number one happens again.
4. HOWEVER when the HDD is not plugged in the fans start spinning and it seems to power up but no POST(beeping) and when i plugged in the monitor today to check if it was booting no display came up.
5. so i remount the RAM and the VID card to no effect.
6. so i'm concluding that its either a faulty power supply or my mobo is fried. =(
7. (havent had the chance to plug the HDD into the computer i'm currently using yet to see if its the HDD)

 

well, what bothers me is your not seeing the bios startup on your screen, (your not seeing the memory check and the check for devices by your motherboard). if the beep your hearing is continuous there might be a problem with your motherboard, processor or your memory. If the beep is short, and quits, it might be a problem with your video card. I would swap your memory and your video cards in your other computer to make sure they work. I don't recommend putting parts from your (working computer) in this problem computer. I would recommend the opposite, (testing the questionable parts in the working computer). But ... you say the computer fan doesn't even start when the hard drive is plugged in. that sounds like a protection sequence. The wiring is bad and the motherboard refuses to start. well, test your parts first. then you can narrow it down to a couple of things.

 

ok there is NO beeping sorry if i didnt make that clear
also i plugged the HDD into the working computer (older and slower ) and same symptoms as before... LED light flicks on for a millisecond then it goes off...didnt check the other cards yet

 

i'm a little stumped. I didn't know a hard drive could cause a computer not to turn on. unless maybe there is a jumper, power, or cable problem that's backwards to the hard drive. I'd like to take the working hard drive and put it in the questionable system. But that's real dangerous, because we don't know why the questionable hard drive ruined in the first place and might ruin the working one too. I can't understand why the computer wouldn't go through bios startup with the drive plugged in(using your questionable drive in the working system). i'd like to say the hard drive is bad, but i'm trying to avoid that, until we are sure about all the settings, cables and parts.

 

hmmm ok my new theory is when my powersupply died it took along my motherboard and HDD... that would explain everything... which *****!!! though it did leave all the other cards video, modem, sound, etc. intact... is there anyway to retrieve that data off a bad HDD? =(

 

My guess is that the mobo is OK because it boots without the HDD. If you have another old HDD, try it just to see if the same problem occurs. If it boots with a different HDD, then your HDD is toast. But if it still doesn't boot with a different HDD, then the IDE on the mobo may have been blown with the power supply.

One other question. How big is the new PS. Should be at least 300W. If the new PS is too small and can't handle everything on the PC, then it will simply shut the PC down.

If the HDD is bad, you may want to check with the manufacturer. There may be a fuse somewhere where a technicial can get at it and replace it (most electronic devices are protected by hidden and unhiden fuses).

Good Luck