Uncacheable speculative write combining

Uncacheable speculative write combining (USWC), is a computer BIOS setting for memory communication between CPU and graphics card. It allows for faster communication than the "un-cachable" setting (the alternative to USWC in the BIOS), as long as the graphics card supports write combining, which most or all modern graphics cards do.

Write combining (WC) allows data to be temporarily stored in write combine buffers (WCB) and released in burst mode instead of writing single bits.