My screen goes black when I use the edit -transform-scale tool,
also the background (behind the work area picture)
flashes from black to nothing (grey and white squares)
it started after a reset computer and fresh p/shop download and installation
Update your video card driver from the GPU maker's website. If you cannot update the driver for some reason, then turn off GPU drawing in Photoshop's preferences until you can get a new driver that fixes the bugs in the driver.