Yes definitely. I build and test the windows binaries on my hashfast devices and they work fine (set them up like any other usb device on windows with cgminer as per the ASIC-README). Just download the latest cgminer windows binary 3.12.3... however hashfast are still sitting on their new firmware so you probably shouldn't try until they release that since the newer cgminer is built around the firmware changes and vice versa. It should actually still work though...