ATI Hybrid CrossFireX-supported graphics cards: HD 5450, HD 5550, HD 5570, HD 5670
Your motherboard will support any PCIe graphics card, not just those which support Hybrid Crossfire.
PS: Hybrid CrossfireX is a technology which allows you to link a low end graphics card to the motherboard's integrated graphics chip. What you end up with is still low end graphics.
AMD Crossfire X Compatibility chart