Problems with Radeon 6850 and Dell

[ImNotLikeYou]

Hello, I'm having problems getting my graphics card to work.
I bought a used Radeon HD 6850 Ref design and I can confirm it works because it was tested on another computer.
However, when I plug it into a Dell Inspiron 580
http://support.dell.com/support/edocs/systems/insp580/en/cs/cs_en.pdf
with a Raidmax RX-530SS
http://www.newegg.com/Product/Product.aspx?Item=N82E16817152028
nothing turns on, but lights flash and the fans move on everything, the keyboard mouse and monitor do not start up.

When I plug the VGA cable back into the integrated graphics card, the computer starts again, but is using the integrated graphics card.

Can anyone figure out what's going on here?

 

[MauveCloud]

Your power supply can't provide enough amps on the +12V rail. According to http://forum-en.msi.com/faq/article/power-requirements-for-graphics-cards an HD 6850 requires 25 amps on the +12V rail, but that power supply only claims to deliver 20 amps on the stronger +12V rail. Also, Raidmax is a Tier 5 brand here:
http://www.eggxpert.com/forums/thread/323050.aspx
So it should be replaced anyway.

 

[ARICH5]

the psu gave up....that raidmax is crap...no 80+ efficiency and only 20a on the one rail.

 

[spawnkiller]

disable the intgrated graphics and set PEG as first startup PEG= PCI-e graphic...

Then install the AMD drivers and reboot, you should be ok then

 

[ImNotLikeYou]

Best answer selected by ImNotLikeYou.