Just won't start.

not from a bootdisc or in safe mode.
All was fine shortly before. I came home and it just would not start. the rig usually runs through it's startup by going through the boot sequence with the floppy last. When I hear the floppy check out i know it's okay. There is no display on the monitor at all when I try to start and no beep like it was before.
I installed new drives back in August. Presently it has a 200GB Segate Barracuda, 250GB Seagate Baracuda and a 40GB Maxtor I use as a scratch for Photoshop. I have tried starting with all drives disconnected except for the OS drive, I have swapped out all of the memory and ran just one dimm still nothing. It is getting half way started and I believe it might be the OS drive again. I went out and replaced the video card and still things are the same. All was fine and nothing unusual has happened. I had been seeing a flicker on the monitor for awhile now is why I replaced the video card.
the board, PS and processor are about 2.5yrs old.

here are specs:

Soyo Ultra Dragon
P4 2.4GHZ Northwood
1.75GB DDR RAM form Crucial
ATI Radeon 9550 w/256 RAM
running Win Xp Pro Sp2

the power supply is 300w
most everything is on board too and the board has RAID though I just use the slots as EIDE.
I do have an old lucent modem card that could have failed installed and I have already taken out the tv tuner.

any help would be appreciated guys.

 

When you say won't start, do you mean no case fans start etc?

If so it could either be the power supply or the motherboard I'm thinking.
Try it with just the motherboard, processor and ram connected, nothing else.

 

The case fans all start up. The fans on the heatsink, video card, bridge and of course the case fans all start.
The power supply was my first thought.
There is a bit of bank over here so whatever needs to be replaced is not out of the question.
I just don't want it to be one of the harddrives. I've disconnected all of the drives and started with just one and it is still the same so I am ruling out a drive problem. I'm going to pull the battery to reset things and see if that helps then I will pull the C drive and try to get a look at it from my laptop with an external enclosure.
It does look like I might have to do the PS, MB and/or CPU or all three and just rebuild. again.
Like I said I have gotten 2.5 tough years out of the PS, MB and CPU already.

does it at least sound like I am on the right path?

 

I had a similar problem recently. There's a good chance the motherboard is just out of lives.

 

your getting a picture on the monitor?Does the comp shutdown around the time the windows screen loads,if so this points to a driver problem

 

I ruled out the drive problem straight away, wouldn't worry about that.
Check out your motherboard, try another psu from a friend if you can. I'm 80% sure it's the motherboard right now, because if you had no drives it would still post with something on screen, thats optical rom drives and hard disc drives. Did you try it with just motherboard, cpu, ram and video card? Take out all other cards, see if anything comes up. Take out the gfx and see if you get the typical error beeps.
I'm sure resetting the CMOS as you suggested could possibly work, leave it out for about 20 minutes though to ensure a full reset.

 

Nothing at all,my bad