No POST but turns on after a "warmup"

[Taint]

Hey guys, I'm having trouble turning on my computer. Most of the time when I press the power on switch on my computer, the fans would turn on (really fast) but no POST would occur and no beeps. Only after pressing the reset button several times over a long period of time (5 minutes) would the PC turn on. I think it might have to be "warmed up" in some way so that it is able to turn on. I thought it was a problem with my mobo, so I RMA'ed it and re-installed it but to no avail. My computer still doesn't POST. My specs are:

Asus M2N-e Motherboard Socket AM2
4200+ dual core AMD Socket AM2
512 MB Gigabyte Radeon 1900XT
X-Fi Audigy Soundcard
550 Watt Antec Truepower 2.0
2 - 1 GB each Corsair DDR2
1- 250 GB Western Digital HD SATA (currently on SATA 1)
DVD drive NEC (currently on cable select as master)
3.5" Floppy Sony

I thought power might be a problem so I unplugged my fans and my harddrive (since I heard you can still access the bios even without the HD) and that didn't work either. Finally I tried to reset the CMOS and that didn't do anything. I don't know what could be the problem since it starts up without problems sometimes, and other times it doesn't start up at all.

 

[Law]

I've seen this problem before from what you are describing. It might be related to the video card and the monitor. Someone told me to leave the monitor off before a cold boot until that single beep occurs then turn on the monitor. I donÂ’t know why but sound quite strange.

 

[Taint]

I had nothing to lose, so I gave it a try. I turned off the monitor, turned on my computer, and then after the beep I turned on the monitor. Still nothing happened, but I did make a break in the case. It turns out when I took out my 512 MB Gigabyte Radeon 1900XT and unplugged its 6 pin power connector, the system turned on. Now I have a dilemma because I'm not sure if its a faulty videocard or a weak power supply.

Note that after the computer is warmed up for about 3 minutes and I press reset, the computer will turn on.

 

[Taint]

I posted this topic in another forum and they suspected that it is either my videocard or my power supply. When I take out my videocard and its 6 pin power connector, the computer turns on without any problems. However, when the computer has the videocard in, the computer is unable to POST unless it is warmed up after a few minutes (then resetting it). Here is my update reply for said forum.

So if it is my power supply, here is the specs:

Antec TruePower 2.0 ATX12V v2.0
550 Watts total
+5V Max of 40 Amps
+12V1 Max of 19 Amps
+12V2 Max of 19 Amps
+3.3V Max of 32 Amps
-12V Max of 1 Amp
+5 Vsb Max of 2 Amps

I'm not a huge scholar at PSU's but I checked my Videocard's website (Giga-byte 512 MB Radeon 1900xt) and it said that it "recommends at least 450 Watt system with a +12V line to have 30 Amps." I know the +12V1 and +12V2 are used for SLi but since I don't have SLi nor Crossfire, are the above amperages OK? Do the amperages combine to form a 38 A or just two different 19 A rails? If so then why does the computer still not turn on with the videocard in, but when I take out the videocard, the computer is able to start wholeheartedly. All I know is that when the power is pressed the fans spin superfast (on the videocard possibly the rest of the mobo too). Except when it passes the POST test when it is "warmed up" the fans slow down considerably. Is it because of the videocard or because the a cold booted PSU is unable to handle the amount of power necessary to fire it up but OK after it is turned on?

 

[Casalen]

I don't really know anything about this; however, I do know that when a motor spins up it takes sometimes twice as much power as it does to maintain. You could be on the right idea, but I don't see how that warm up would make any difference, as the components still want to activate together. There could be slightly less draw needed if the spans are still spinning a little bit from momentum, but that seems really unlikely, especially considering that you have a good sized PSU. Anyway, all I can really contribute is that your last comment, that the cold boot might have too much load, does make some sense.