Could anyone tell me if these cards are compatable with iclone 5.

1GB DDR 3 Nvida GeForce GT 520 (DVI,HDMI,Vga Adapter)

1GB DDR 3 Radeon HD 6450(DVI,HDMI,Vga Adapter)

While both graphics cards are compatible with iClone5, the results you would get would be very poor. Both cards are low powered and not really suitable for 3D graphics work.

In general, when it comes to graphics cards, it is the second digit in the product number that is important and the higher the better. So while an Nvidia 580 will give great performance with iClone5, the 520 you mention above will struggle unfortunately. Likewise for the Radeon.