ATI Radeon 5850 , PC will not POST mobo GA K8N Pro Sli

[Myopik]

New ATi 5850 to replace nvidia 7900GT\GTO . 
I've removed old drivers .....powered down ...removed old card ..inserted new ATI 5850 and powered up .

Machine starts ...but no bios video .....hard drive stops spinning ...permananet red light......all fans on ...but still no POST and Bios .

PSU is Cooler master 500w peaking to 650w which should be OK

I can switch back from new card to old card Nvidia 7900GT\GTo everything is OK ...POST , Bios and boot to XP

Have checked for latest Bios on board , with gigabyte say is F10D which I am already running with .

Dead ATI 5850    Bios issues ??   Compatibility issues with GA K8nPro Sli ?

any opinions or help please

[Dark Mantis]

Clear CMOS and load BIOS defaults. Check card is stiing in the right slot and positioned firmly. Check extra power cables to card are installed.

[Myopik]

thanks for the advice

I cleared the CMOS ..battery out for 10mins ......set bios to defaults

Also disconnection CDromDVD drive and extra cooling fans on case...just in case power is the issue.

powered on ...still no Joy    No POST NO BIos .

Put old Nvidia back in to slot and ..Boots no problem.

What do you think card Saphire HD 5850  is faulty ?

BTW - mobo GA KN8 Pro Sli are PCI -E slots =2.0 ?

[Dark Mantis]

That could be your problem that is an old board and the PCIe slot is only v1 I expect. Check on the website and see the specs.

[absic]

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