ATI HD 5850 not working under windows 7

[cdthomo]

Hi guys,

now I have googled this and specifically searched this forum but answers are old and very diverse.

I have an acer M5201 desktop running AMD 9550 2.2ghz, 4.00gb RAM, 500gb hdd and a 400watt PSU (I know this is low but I have had the card running and doing some heavy computing using ubuntu).The OS is windows 7 ultimate 64 bit.

There were no graphical issues with the 9800gt or the built in graphics.

The problem: computer starts with HD5850 installed, displays POST and BIOS screens if requested, shows "starting windows" screen then display is stopped with the monitor switching to sleep mode. The card is mounted properly and has extra PCI-E power connected. Computer stays on with HDD light intermittently flashing. There are no beeps or obvious error messages at boot and the symptoms are identical every time and not "unstable" crashes.

1. uninstalled the nvidia drivers via control panel - no change
2. run driver sweeper and removed all registery links to NVIDIA - got to desktop but then screen went off around about the time windows started installing its generic graphics driver
3. booted on built in graphics and installed the most recent ATI drivers - no change
4. tried to do a windows 7 repair install - got to preparing windows status bar then screen went off as this hit 100%
5. booted with graphics card into ubuntu - no problems, ran cgminer @ 330Mh/s and only got hot, didn't crash.

What is windows doing wrong and how can I stop it doing it?

Thank you for reading all that, wanted to make sure I covered everything!

 

[alyoshka]

Looks like you first need to check the card out in another rig and confirm that it works.
If it does, then , it looks like you need to do a clean install of the OS from scratch.

 

[cdthomo]

Hi alyoshka, the card works on this rig under ubuntu and on my barebones ubuntu server. I tried to load the windows boot installer with the 5850 fitted but the same thing happened!

Should I try the reinstall on onboard graphics then try installing the card?

 

[alyoshka]

Something a already caused a problem with the files ( drivers and hardware ) in the pre-existing OS. That's why the requirement to do a clean install.
I can understand it working under Ubuntu, but the base OS is some how unable to set things back right as they are supposed to be.
Yes, you could try the reinstall, but only if it is conflicting with the other GPU adapter, otherwise it's going to be a try in vain again.