New Power Supply; ....Still Nothing

[Glassin]

Hi Guys,
My computer was having restart problems ( kept rebooting during startup; abnormal fan noise) so i decided to tear it down and clean it 1 last time before I replaced the power supply as I've done many times before ( 2 dogs = lots of dust!). This time the power supply is working but nothing else so I got a new one and installed it. Same thing - no POST. I checked the memory in another computer and they're fine. I reset the CMOS battery - still nothing. All my fans are running ( PS, Heatsink, AGP card). does this sound like a MoBO failure? I tore it down again and re-installed everything to double check myself but couldn't find any problems. I know I'm working with an antique but here's the specs:
AMD K6-3D 400 Processor
VIA MoBo - VT82C598MVP
Award BIOS

 

[edfair]

Sounds like power problem. Processor can't operate till power good comes up. Select switch on 115v? Unplug the drives to reduce the load and see if it comes up.
How much power do you have? Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[Glassin]

That's what I thought too. I changed the power supply from a 250 watt to a 300 watt; pulled everything and re-installed memory and agp card and made sure the voltage was set at 115 on the power supply and still have the same results.

 

[GrandpaCarl]

To what extent is nothing working? When you first power on, do you get a disk access at all? Do the old auto mechanic trick and place long screwdriver against hard drive and then handle right against the bone behind your ear. You should hear the disk spinning, and head loads, etc.
Look at the keyboard lights, and see if they flicker. If you see any activity, but nothing on the monitor, it could be that the monitor cable is not snug or is bad, or it might be that the video card needs to be pulled out and reseated securely, or it could mean that video card is bad.

Substitute another monitor and/or another video cars, if possible.

 

[Glassin]

I'm sorry I should've let you know in the first post that I've changed the video card, cable and monitor to no avail. I also should've said that the keyboard does flash and the hard drive is spinning. There is no picture and no beeps at all.

 

[edfair]

ATX? If so pull the powerup switch leads and momentarily short them with a screwdriver or something metallic.
ATX needs a power-on signal to turn the power on to everything but the keepalive circuits.
From the description I don't think you have ATX, but not certain. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[Glassin]

I'm afraid it's an AT (the 'antique' I mentioned before).

 

[edfair]

OK. Requires power good to let the oscillator run. How about reseating the processor and memory again. In fact rock the memory 5 or 6 times before you lock it in place. And pull the reset switch connector off the board. In fact pull all the connectors off the board, including IDE and floppy. Then see if you get a splash screen. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[Glassin]

I'm afraid I already tried that - tried something new today and really it was quite simple. I picked up a new ATX case, power supply, motherboard/ 1.2 Gig processor and 512 megs of PC133 RAM and now it works fine!

Thank you Ed Fair and Grandpa Carl for your help - I know I'll find some other problems sooner than later!

 

[edfair]

So the pressure is off. Now you can fix it for practice and get some network practice. You gotta do what you gotta do. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[Guest_imported]

Try reducing the speed of the processor to say 350 or even 300MHz. I've had some dodgy K6 400's in the past that would no way run at 400!


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