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Help! Changed PSU, now it won't power up at all with new or old one.

By jacksbloodyface
Aug 19, 2005
  1. I changed my PSU on my Dell Dimension 8300 to a Antech 350W. Along the way I tried to put the mobo in a different case that came with a PSU, in the process removing the CPU. I'm new to all this so I dont know if I majorly screwed up or what, but since that didn't work, I put everything back in the Dell box, returned the case, bought the PSU, stuck it in the dell, (with a little modification of the case so the outlet could be accessable) and then tried to power up. Nothin, nada. I thought I may have not seated the CPU properly so as I hit the power button I applied a little pressure to the heat sink, and the fans started sputtering and I heard a few nasty beeps before it stopped altogether. Now its as before, except nothing will stimulate that little response. Please, any help or ideas would be greatly appreciated, I don't need a dead computer right now, no money to replace it (just spent more than I could afford on the video card and PSU).
     
  2. RealBlackStuff

    RealBlackStuff TS Rookie Posts: 8,165

    That PSU is not compatible with the crappy Dell motherboards.
    Dell have their own, proprietary, PSUs made, and they use different wiring from anybody else.
    Buy a new, standard motherboard that can accommodate your current CPU and Memory. Everything else should fit the way it is.
    You'll have to reinstall Windows and the rest from scratch (NOT with any Dell recovery disks!)

    Alternatively, compare the wire-colours on the 20/24 pin connector that goes to the motherboard. Change the Antec PSU wiring according to the Dell PSU wiring, and you might be lucky. It's a bit of a fiddle, but should work.
     
  3. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    I don't believe the power supply is proprietary, I got it up and working by taking out the battery on the mobo, and waiting, then reinserting and putting it back together 30 min later. But then I got the yellow light that something's not working. I reseated the cards several times, then I reseated the cpu, and now it won't respond to power once again.... ARGH.
     
  4. i_need_answers

    i_need_answers TS Rookie Posts: 144

    I've had a simular expirence with a HP Compaq. I don't really know how to solve your problem but if you want the illussion of progress try unplugging the power cord to your PSU for about 10-15 seconds. Then reinsert it and when you either reinsert it or hit the power button your fans and stuff should spin for like 1 sec. I think it has something to do with the capasitors discharging if they can discharge that fast I dont know. Anyways this might help you figure out if the DELL PSU is propritary :-( ugh. Must everything DELL is.....
     
  5. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    The PSU was working, all fans going, drives turning on etc, except for starting up(steady amber light, ie. some component not functioning), until I decided to reseat the CPU, now its back to doing nothing at all.
     
  6. meettaco

    meettaco TS Rookie

    your getting way to ahead of yourself. If your motherboard doesnt even get power it has nothing to do with your cpu or other things not "seated" correctly. Like the previous person stated you should never try to change powersupplies on a board that uses its own psu's. y did you take out your battery. Thats the only thing that keeps all your bios settings saved. Sounds like you got way ahead of yourself without finding any info out before you did it. Good luck to you, but it sounds like your system is screwed....
     
  7. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    No need to be condescending man, even though I may deserve it a bit, I'm up to my neck in **** here and not really needing any more of it. If you weren't, sorry, but I'm a bit tense at the moment. I removed the battery because I had read another board with someone having a very similar issue, and it appeared to work for me, the first time. I didn't think it was an issue with my power supply because it worked for a time, until I messed with the CPU the second time, but I guess thats good to know that I should be paying attention to the PSU's connections and not anything else. The reseating of things was in response to the amber power light, indicating some component wasnt working or was installed improperly, AFTER I got the PSU to work. From all of the documentation I have read online, the PSU is NOT proprietary, and should be replaceable with standard ATX PSU's, and when I've been having problems, theyve been identical for the replacement and the old PSU. So, the questions remain:
    1. Whats causing the computer not to respond to power
    2. If I get that to work, what's wrong with it that it won't boot (nothing to monitor etc, just amber light on the power button rather than green, didn't seem like the CPU was doing anything, but the rest of the components seemed to be working, ie DVD drives, HDD etc.)
    3. What damage may I have done to the mobo by removing the battery and what do I do about it.
     
  8. i_need_answers

    i_need_answers TS Rookie Posts: 144

    Hey,
    The PSU can still be bad even if it worked for awhile. How many watts was your old PSU? Sounds like you kinda need a new PSU with more watts.
     
  9. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    Highly doubt the PSU. Last night, I removed the motherboard battery, waited 30 minutes, put it back in, plugged everything in and turned on. Both the new and old PSU worked, but the computer did not start up, just the drives, fans etc. worked, nothing to the monitor though, and no CPU or hard drive spooling sounds.
    I reseat the CPU, now its back to how it was before the battery removal, neither PSU does anything. Little green LED on the mobo turns on, but when I hit the power button, nothing happens, with either PSU. I didn't replace the PSU because it didn't work, I replaced it because I got a GeForce 6800 and the old PSU couldnt cut it. Now I'm stuck with a dead box, as before, nothing happens with either PSU except that little LED. I've checked and rechecked the connections over and over again. I don't think its the PSUs because when it worked, it worked with both, when it didn't work, it didn't work with either. Any more ideas?
     
  10. meettaco

    meettaco TS Rookie

    sorry if i sounded condescending. Lets back up.. can you post your system specs. why where you changing the psu in the first place? theres a good chance it could be hardware related or bios related. do you have other hardware to test or swap out things with. Like a different video card or ram or processor. when you reseated your processor did you put thermal paste back on the heatsink and fan? is everything plugged in right? it just doesnt sound too good at this point....
    its tough to isolate your problem without some more info. It just sounded to me that you atrted unplugging things hoping for a solution. You have to isolate each problem. It can be a friggin headache.
     
  11. vnf4ultra

    vnf4ultra TechSpot Paladin Posts: 2,195

    My dell 2300 isn't proprietary, my antec 350w fit/works great.

    Old dell's did have odd psu's though.

    Has your pc ever worked with the new 6800? If not, then maybe the v card is DOA, I've seen many people get bad cards, many people seem to have issues with nvidia 6 series being doa, maybe it seems that way since they're popular, but neither of mine were doa(6200, and 6600gt).
     
     
  12. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    Its a Dell Dimension 8300, 2.66 Ghz P4, 1 gig RAM. I just purchased a GeForce 6800, and since my machine only had a 250 Watt power supply, I decided to change it for a bigger one, as from what I read online it was standard ATX and replaceable. My problem started when rather than getting just a PSU, I got a case with a PSU installed. I thought my mobo was ATX, but it apparently wasnt as it didn't fit into the case. I had no intention of messing with it this much, but it was necessary to take the CPU off to get the mobo off its mounting plate. When it didn't fit, I put it all back together in the Dell case and took the new case back, in exchange for a new PSU. I come back, put in the PSU, and after all the connections are back together, it won't start up. Nothing, the only sign of life is the little green LED on the mobo. I go over all the connections to make sure nothing is missing or loose, nothing there. I thought perhaps the CPU wasnt seated all the way after putting it back on, apply a little pressure to it as I hit the power button and it makes a beeping noise for a couple seconds before stopping. I took out the CPU and reseated it, further causing problems when I noticed it didn't go in perfectly and some pins were bent. I spent many careful minutes getting everything back straight, and it now seems that it is seated properly, as it was before, I don't think that was the initial problem, though I may have damaged it in the process. Don't think so, but its a possibility. So, I read online that removin the PSU, taking out the battery, waiting 30 minutes, putting it back in, and plugging it all back together might do the trick in this type situation. I did this, and lo and behold, it worked. Fans spun up, power was obviously getting to places, but the power light on the front glowed amber instead of green, and no signal went to the screen. All the drives worked, but it obviously wasn't going through the startup process. I thought perhaps the video card wasnt seated properly, as this was what Dell recommended online when you get a solid amber light, and messed with that for a while. Then stupidly I thought again to reseat the CPU, thinking it wasnt all the way in, which I did, and it hasnt displayed a sign of life since.
    I have both PSUs, both functional, both Video cards, but it doesnt seem anything obvious will now get it to turn on or exhibit any sign of life with any of them. The battery thing did not work the second time, so I'm stumped, pissed, and out of ideas. Thanks for the help, hope this gives you some idea or flash of insight, but I may be left just to take it somewhere to repair, or just get a whole new goddamned CPU, mobo and case....
     
  13. vnf4ultra

    vnf4ultra TechSpot Paladin Posts: 2,195

    Just a note, I know how you feel. It's happened to me several times. Things just won't work when they should work, and it drives you nuts, and you're at your wits end. I don't seem to think as clearly when I have a problem, due to the stress, and it usually ends up being something not too hard to fix.

    Any possibility that the motherboard could be shorting with the case? Have you tried booting with the board outside the case?
     
  14. i_need_answers

    i_need_answers TS Rookie Posts: 144

    Hi,
    CPU pins are just to easy to bend.... Sorry about your problem and I understand your frustration. I've bent CPU pins more than once and im sure LOTS of other have also. Congrats on getting them all straight. Sounds like your CPU is probably fine though. I'm still kinda worried about the 350 watts... But you don't seem to worried about that so it's either the motherboards fault or the CPU's fault. I'm guessing motherboard. In my simular experience I bought a new case, it worked about a week then died. I took out the cpu, bent about 5 pins and felt like throwing my PC out the door. Anyways What I did was take a needle (this is incase this helps anyone) and inserted it under the bends then pryed the pins up straight. Works great on socket 478's. Well once I got everything back together it still didn't work. I bought a new MoBo and that didnt help. Finally I took out the PSU that came with the case and stuck in my old one. Comes on first try.
    My problem was a crappy PSU but that might not be your case. But DEFF. try it outside of the case first. If you need to turn it on without a switch you can use a paper clip on the powerbutton jumper.
     
  15. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    Thanks for the replies. I have tried starting it up out of the case, but am not totally sure how to short the power switch. The larger issue though is I can start it out of the case, but to be fully sure I'd probably have to take it off its mounting plate, which is a gigantic pain in the ***, and probably was what started this whole mess. I guess that would mean that probably leads to the solution, but I'm still uncomfortable with doing that because I already did some damage the the plastic pins holding it on, and don't know how much more they can sustain if I have to take it off again. I doubt its the new PSU, as its an Antec True Power 430W and I doubt likely to be defective, but as I said before I've tried both. I guess I should now try and start the thing up out of the box, off the plate. What minimum should I have plugged into the mobo to do this?
     
  16. i_need_answers

    i_need_answers TS Rookie Posts: 144

    Oh well I was thinking it was a 350 watt 430 should be fine. I would try memory, CPU and PSU..... Just connect the two pins that the power button switch connects to with a paperclip to start it....
     
  17. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    Well... a pin finally broke. I think I'm now totally screwed, and the thing hasn't let out so much as a blip in 24 hours... Time to start looking for new mobo, cpu and box.... (and a month ago I had paid off my credit cards....).
     
  18. i_need_answers

    i_need_answers TS Rookie Posts: 144

    Yep.
    you'd think there could be a better way then a million tiny pins. Oh well thats how life goes. Good luck with your next computer build.
     
  19. vnf4ultra

    vnf4ultra TechSpot Paladin Posts: 2,195

    Try socket 775 cpus, they don't have "pins" per se.

    How did you break a pin off though? Drop it? Force it in really hard? It should take no force to get the cpu in, if it does, you don't have it aligned right.

    I saw a guy that soldered a pin back on a cpu, but I don't remember where. That'd be some awful precise soldering though.
     
  20. jacksbloodyface

    jacksbloodyface TS Rookie Topic Starter

    My Dell mobo has an assembly that holds the CPU on thats really hard to get the CPU in and lined up properly. I had not had too much trouble with it, but the pin bent in a shape that would not align with a pin or knife, so I used a very small tweezers, which resulted in its breakage.... Bad bad day.
     
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