guys i have a friends pc here with a faulty graphics card that needs changed, but how the hell do these 4 spring screws work, i dont want to break anything so thought id ask how to remove them, cheers if anyone can help.
Just unscrew them, they are sprung so only a certain amount of pressure pushes the heatsink onto the chip, the screws will only have so much thread, once that's used up the springs apply even pressure.
Just had a closer look, same applies but you would release the pins from the print side, That's not a card though, are you replacing the graphics BGA chip ?
You'll have to completely remove the PCB to get to the underside. Push on the pin to release pressure on the clip, makes it much easier to release. Shouldn't matter too much, but try to remove the clips in reverse order, i.e. 4, 3, 2, 1.
As #parker13 says: You're not going to find a graphics card, but a GPU soldered directly to the motherboard. These are not intended to be user replaceable.