XFX RADEON HD 4890 XFX Radeon HD 4890 review also featuring the Gainward Radeon HD 4870. XFX Radeon HD 4890 has a 11% higher clock speed, 9% higher memory speed and the same 800 Pixel Shaders as the Gainward Radeon HD 4870. This means the XFX Radeon HD 4890 will be atleast 10% faster than the Gainward Radeon HD 4870. Another advantage for the XFX Radeon HD 4890 is the extra 512MB Memory which will definately increase game performance."