My brother recently tried putting his 5770 in his computer. This is all inside this case(http://www.newegg.com/Product/Product.aspx?Item=N82E168...). Specs to best of my knowledge:
2.4Ghz Quad Core CPU
4GB DDR2 RAM
Since the 300W PSU couldn't power all of that and the 5770, he got one of these(http://www.newegg.com/Product/Product.aspx?Item=N82E168...) just for the 5770. After hooking everything up correctly, and pressing the power button on the PC, everything seems to turn on(including the 5770 with its loud fan), but there is no signal to the monitor. He tried both DVI slots on the card, but neither of the HDMI slots. He also tried a different monitor. I honestly have no idea what the problem is and would really like to get this resolved ASAP so I can be done helping him with his PC problems. Any feedback is appreciated. Thanks ahead of time.
He tried the card in a different computer and it worked fine. He also tried using a 6600gt in that slot and it worked...so any other ideas?
After trying the 6600 did you remove the video card drivers ? - could be the system is thinking the ATI 5770 is being seen as an old FX57xx series Nvidia card ( I know some games autodetect will do this causing it to set to ultra low settings and disabling most of the shaders) and using Nvidia drivers instead of ATI's. try restarting with the 6600 and then before shutting down switch to the generic VGA driver in windows and uninstall all of the Nvidia drivers - shut down and swap out the cards - restart and install the ATI drivers.( or try booting into safe mode removing the video card drivers and reinstalling them.)
With the 6600 in, I manually uninstalled the nvidia drivers. I then booted into safe mode and ran driver sweeper, checked off all the nvidia stuff and pressed clean and rebooted. After taht, I installed the latest ati drivers and then powered down and put in the 5770. Still no luck. What could it be? My brother says that he gets a signal with the 5770 when the HDD isn't connected, so I really don't have a clue here.