no display after changing graphic card

[PYOP_QC]

Hi! I have a old pc woth xp, and i decided to change it for win 7 with success.I've installed all the drivers except the graphic card.

...But,I think I did a mistake because my screen was plugged into my vga graphic card, and I decided to replace the graphic card (that worked well) for another graphic card that someone gave to me and a didn't have display. So I took the initial graphic card that my pc had (because it was working 5 min before) and no display on my screen and this is brought me a lot of prob. The fan of the Cpu and graphic card are spinning well and my led on my motherboard is turn on, and I'm not sure whats part in the pc is the problem.

Here is all what I tried to resolve the problem:
1- I have unplugged all parts except the 12v, the 20 pins power and one strip ram and turned on the pc, there are just the fans spinning.
2-I've clear the Cmos by withdraw the battery Bios. No display when i turn on the pc.
3- I've tested all slot ram in the differents slot, no display, and whitout ram, no beeping, and i'm sure i have a intern speaker in my box.
4- I tried other screen, no display..

Do you havr some other suggests? Or ideas of what is the problem? Because I really want to repair that pc . mainly that the GPU was working before i changed it for another.

 

[i7Baby]

What was the old graphics card? What is the new graphics card? When you installed Win 7 did you do it with a disk reformat?

It's just that your drivers might be missing. You need to put back the old card - I gather it still works. Then update all your drivers - Go to Device Manager in Control Panel and click through every item and get it to update driver.

When everything is working with the old card and all the drivers are updated, try installing your new card. If the old and new are similar then with a bit of luck Windows will update the driver for the new card when you fire up the pc again.

 

[PYOP_QC]

The graphic card that worked when i installed win 7 is a nvidia 180-10050-0000BQ4. It's since i replaced this card by another that is an Ati All-in wonder 9600 ( that was not working )and I put back the nvidia that its became black screen, when ibturn the pc on, the green led on my screen turn on but 5sec later , it becomes yellow and fall in off mode , I cant access to the Bios

 

[PYOP_QC]

But im not sure model of the nvidia's card

 

[PYOP_QC]

And its two old agp graphic cards, with 128 Mb i think

 

[aldan]

does your computer have onboard graphics by any chance?

 

[PYOP_QC]

Nooo.. Unfortunately

 

[aldan]

crap.you know it doesnt sound so much like a graphics card problem.i would go in and check to make sure all power and data connections are tight.you may have inadvertently loosened something while installing the video card.unplug and reseat all connections and see if that helps.

 

[PYOP_QC]

But when i changed the graphic card, i didnt touch anything else, thatbwas just the graphic card... Its so weird. And I tried to unplug and plug everything, im sure that all the connections are ok because the pc turns on but there is just no display.. Its sound like the motherboard.