Every time I play a game, I get the frozen-screen treatment—sometimes right away, sometimes a few hours in. I get a weird checkerboard pattern on the screen and I can’t Alt+F4, Ctrl-Alt-Del, or anything else but a hard restart to get back to Windows. I’m running 32-bit Windows Vista, an AMD Athlon 64 6000+, a Sapphire Radeon HD 4870 Vapor-X, 4GB Kingston Hyper-X RAM, and two 1TB hard drives, all inside an Antec Nine Hundred case. I’ve tried running with the side of the case off and a fan blowing on the card, even though with the case closed I get cool air out of the back, so I doubt heat is the issue. I’ve reinstalled video drivers countless times and the forums don’t seem to be much help since I haven’t seen a thread describing the same error I get.
Read the Doctor's advice for Chris after the jump.
The 55nm RV770 is one of the best arrows in AMD’s GPU quiver, so it’s a good thing the part has proven to be both versatile and powerful. As deployed in the Radeon HD 4870, the RV770 has a full complement of 800 stream processors—just like the Radeon HD 4850—but in this design, the GPU is paired with GDDR5 memory.
GDDR5 memory boasts a very high data rate (ranging from 3.6Gb/s to 6.0Gb/s, compared to GDDR3’s 1.0Gb/s to 2GB/s). This enables AMD to deliver nearly the same memory bandwidth through a relatively narrow and inexpensive 256-bit bus as it would with a much wider and costlier 512-bit bus.