Help! New Graphics Card red characters and black screen on startup!

[GrimAnims]

Ok so I got a new Radeon HD 7950 yesterday to replace my 7750, but when I installed it and turned on my pc I got this: https://www.youtube.com/watch?v=A8cAwT7qojs&app=desktop

The mobo logo flashing usually happens, but the red characters at the top and the fact that the screen just stays black afterwards is wrong.

I highly doubt that my GPU is broken seeing as how I JUST bought it. My specs are: AMD FX 4350, GPU listed above, Thermaltake 500W PSU, and 8 gigs of ram.

Could the psu be too weak to give adequate power to the GPU, or is it some other issue? The 7950 is noticeably larger than my 7750 so the only possibility I can think of is that. Help?

EDIT: it's not the power supply. I got a new 750 watt delivered today and I'm getting the same thing

 

[akseli]

What Windows you have? Try booting and pressing F8 or shift+F8 if you have W8. I think you need to change something in UEFI or W8.
http://www.adventcomputers.co.uk/product-support/faq-windows-8-uefi-and-graphics-cards-updated


I don't think the problem is the secure boot mentioned in few places or UEFI capable video BIOS, but something else that has to be reset for the computer to correctly recognize the new graphics card.

 

[GrimAnims]

What Windows you have? Try booting and pressing F8 or shift+F8 if you have W8. I think you need to change something in UEFI or W8.
http://www.adventcomputers.co.uk/product-support/faq-windows-8-uefi-and-graphics-cards-updated


I don't think the problem is the secure boot mentioned in few places or UEFI capable video BIOS, but something else that has to be reset for the computer to correctly recognize the new graphics card.

I have windows 7. When I press F8 on startup I get "please select boot device: my hdd, cd drive, or "enter setup"" all enter setup does is take me to my bios screen, and I'm already booting from my hdd

 

[akseli]

I have windows 7. When I press F8 on startup I get "please select boot device: my hdd, cd drive, or "enter setup"" all enter setup does is take me to my bios screen, and I'm already booting from my hdd

F8 should open Windows boot menu in Windows 7 too, I'm not sure if it should display other boot devices there. Anyway try to boot into safe mode.
The menu should be something like this:
http://pcsupport.about.com/od/termsag/p/advanced-boot-options.htm

What you describe, sounds like bios boot device menu. It's usually tied into different button to avoid difficulty, like F10 or F12.

Usually changing the card should be very easy, but sometimes the system, or windows, may fail to boot. Your system boots so hopefully you can get into Windows safe mode, where you can either try to change the graphics drivers, or delete the old one, forcing Windows to recongnize the new card. Maybe the new card is too similiar and Windows tries to use it with old drivers, which would not work.

If you can't get into the Windows boot menu by pressing F8 like shows inabove website, try pressing it liittle bit later, as the screen goes blank, as your motherboard might use the same key for it's own menu. But pressing it too late, won't work either, there's only a short period of time when it can be pressed.