I believe Asrock is the budget arm of ASUS. So if you're a brand-buyer like me that makes some difference.
The ASUS I listed also has a USB 3.0 header if you're planning on using a front panel USB 3. The ASUS has more fan connections and a very handy MemOK button on the mobo to check for memory compatibility issues.
If you open up the two side by side on these links and click the Details button, you get a good side by side view of some of the technical differences.http://www.newegg.com/Product/Product.aspx?Item=N82E16813131792http://www.newegg.com/Product/Product.aspx?Item=N82E16813157271
Are those features worth $55 to you? Only you can answer that one
Your card requires a PCI Express 2.0x16 which both boards have.
Don't forget your motherboard speaker so you can hear POST beeps http://www.amazon.com/PC-Internal-Mini-Onboard-Speaker/dp/B002W4M0DW http://www.amazon.com/PC-Internal-Mini-Onboard-Speaker/dp/B002W4M0DW
Also, the Asrock supports old timey keyboard/mouse connects (PS2) while the ASUS requires USB. I had to buy another keyboard with the ASUS.