When i overclock my Graphycs card and restart PC - slider disappears. More precisely the minimum value of the slider becomes equal to the value set forth acceleration. If I put the maximum value, the slider just disappears. This is only a memory overclocking slider. This problem with Overdrive interface in Crimson 15.11 and 15.11.1 Beta. And why driver detect my graphics card like radeon r7 200 series? My card is SAPPHIRE Radeon HD 7750 1GB 128-bit GDDR5. My system spec is Windows 10 x64, Intel core 2 duo E7300@3600mhz, 4 GB DDR 2 800mhz, Asus p5ql Pro motherboard, BIOS Version 1004. And sorry for my bad English.