video card blackscreen

[Zoner7]

Hey! I recently purchased a new video card hoping to make my current computer run games a little more smoothly until I buy a new one. I ended up buying a pre oc'ed Leadtek A6600 GT TDH, and I also bought a new power supply (a Raidmax 450yx120 450W) to provide enough wattage for it to run.
So I installed the new PSU with few problems, but after installing the video card, my computer refuses to start up. When I attempt to turn the computer on, sony screen loads and then the monitor basically goes black. I've tried all sorts of things to get this video card working: I've tried replugged everything, I've messed with settings in the bios, I've tried disabling the integrated video card (through windows... I coulden't figure it out in the bios) on my computer, reformating my computer and nothing has worked so far. Anyone have any ideas about how to fix this thing?

Some Specs:
I'm currently running Windows XP Home Edition on a Sony Vaio PCV-RX850.
2.4 gigahertz Intel Pentium 4
My motherboard is a ASUSTeK Computer INC. P4S533VX REV 1.xx (no idea what this means. I just saw in another post that people asked for it).


I know the motherboard supports AGP x8 chips and I have ample power. What's going on here?

 

[Tedster]

You cannot disable the onboard video in windows. This is only a windows disable. You must do it in BIOS. Enter BIOS by holding DEL or F1 or some other key (see your manual) when booting. BIOS is not complicated, There should be a menu to turn it off or on.


Plugging in a video card with onboard video still on will not work.
as you see.

 

[Zoner7]

I'm sorry, let me re-phrases myself. I disabled the integrated video card in the hardware manager and hoped it would work. I wanted to do it in bios as well but I was unable to find the option. I think this is because I am running an OEM and there are restrictions implemented in the bios.

"Plugging in a video card with onboard video still on will not work.
as you see" The thing is, I've upgraded my video card before and it worked. I've run both PCI and AGP cards in my computer, neither of which came with it. I was able to install these so I don't understand why this one can't work.