I went from a PNY GTX670 to the Gigabyte GV-N970WF30OC-4GD. My own experience was extremely vexing...to say the least. On receiving the card, I did a normal shutdown... pulled out my very functional GTX670. I installed the new GTX970 and it simply hung at a black screen on first power-on. It was only after rebooting and waiting for about four minutes, that the monitor got signal and the Windows splash screen appeared. That power-on-to Windows splash screen time has gradually diminished over five weeks of use. I still do not get a bios screen at power on...instead it stays black until the splash screen comes up...only now, it's approximately 1 minute. The computer runs great once booted into Windows (i.e...no crashes, blue-screens, instability etc...). My newest issue is I cannot boot into Advance start-up options. It simply will hang at a black screen if I attempt to. I am trying to disable driver signature verification to load a non-certified driver for a piece of hardware not related to the OS. The black/blank screen issue should have been looked at seriously months ago. They're simply too many cases of it happening...across all manufacturers. Gigabyte, Asus, MSI, Zotac...they all seem to have instances of it. It warrants a look to determine the root cause.