No display output while 6670 is installed- AMD A6 Build

[MrChain]

Finished putting a dual-graphics build together, but it will only output to display from onboard when the 6670 I bought is not installed. As soon as i shutdown, install the 6670, and boot up is won't output to my display via On-board VGA or the 6670's VGA and DVI-D connections. Case, CPU, and 6670 fans all spin up, and DVD/Cases power and HDD lights work. No funny smells, arcing noises, nor pop music have been produced by the computer
The motherboard has previously had a nvidia 550 ti installed without a problem.

What I've tried:
-To change bios setting for display initiate to IGP (no crossfire), IGP (crossfire enabled), and PCI Express
-To update the bios to latest available version and then all of the above
-To restore bios to default before and after bios update
-To use a dvi-d cable instead of a vga to connect the monitor
-To get drunk and forget about it


Build is:
an AMD A6-3500
4 GB Crucial 1866 ddr3
Intel 335 240 GB SSD
ECS A75F-M2 (F1)
Rosewill 600 WiFi adapter (PCI 1x)
'Frisby' 350W power supply/ case
Lite-On DVD Burner
Gigabyte 1 GB 6670 (GV-667D3-1GI
Uber-super-mega-edition DELL SE198WFP 19" monitor

This build should stay far from any wattage shortages when overclocked,
running stock settings since I've gotten it

I expect to have to get an RMA on the card, since the power supply should be sufficient and the pci express slot has work on another card, but I'm just throwing the issue out there if there's something i haven't thought of

 

[aebome]

This may be obvious, but since you didn't mention it, have you thoroughly cleaned out the Nvidia drivers and installed AMD's newest drivers? If not, try doing that and see if it helps.

 

[hero1]

You have to uninstall all Nvidia drivers. Do a reboot and then install the AMD drivers.

 

[hero1]

You also might want to swap that PSU, just because it work with different GPU doesn't mean/guarantee to work with another GPU. There are tons of great PSUs for sale and will take future headaches away. Never skimp on PSU if you want your PC problem free. NEVER!

 

[MrChain]

nvidia was installed on a different build....same mobo, cpu, ram, case, psu... new hard drive and win 7 install, so, aside from the fact that the drivers don't even work in dos/boot/post mode, they certainly aren't the issue....
will not display to screen in bios or before choosing bios...let alone getting to windows...just blank

 

[MrChain]

also, according to Xtreme and thermaltake psu calculators, the 550 TI requires ~50 more watts than a 6670... and I'm running the system a stock, it was overclocked when the 550 ti was installed with no issues on the same psu... just fishing for some bios settings options i may have overlooked, or a special ninja tactic of placing it in the pci slot before i admit defeat...

 

[MrChain]

RMA'd back to Newegg..will re-post to this thread when i receive the replacement