I have a computer with AGP4x and I want to get Nvidia geforce 7600GT graphics card for it. The problem is that on some sites it is written that it supports AGP8x and some says it is for AGP 4x/8x. Does this mean that it will work in my AGP4x motherboard? Also, if it does work, will it be operating more slower ?

I can't say for sure if it will work or not, but I have a very similar card and will check it against my older computer tonight if I have time. Any idea of what brand of card you have in mind (BFG, PNY, XFX, etc.)?