So what is the cheapest way to make this setup work? I have Asus F2A55 motherboard and AMD A8 X4 A8-5600K APU. Would any cheap radeon do? Also, can this APU be crossfired with HD5450?
APUs can't be crossfired, any cheap Radeon should work, though I'm not sure why you don't want to use the nvidia card unless its the integrated graphics type, which it doesn't sound like. Just use the nvidia card and enjoy your gaming