If the monitor doesnt work check to see if connected to the new vid card. if not connect it.
If already connected and doesnt work, then plug it into the old vga adapter(assuming u had integrated graphics) and it should turn on. Then go to bios and change it so the graphics is on pci or agp bus depending on the video card. also go to control panel in windows and disable the integrated graphics under display adapters.
if u do not have integrated graphics, put in ur old video card and plug ur monitor into it and follow the same steps.
After all this shut down and plug ur monitor into the new graphics card.
Hopefully these steps should help u fix the problem.
I recently installed a game card but, my monitor won't work..I read one piece of feedback about needing to change the BIOS. I have an Insignia D300. Can anyone tell me...step by step...how to do this?

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