Z68X-UD3H-B3 in combination with Radeon HD 6850

[colt45]

Hi
Configuration:
Mobo Z68X-UD3H-3B with latest upgraded firmware and standard settings
8GB Corsair Vengeance 1600
Samsung 830 - 128Gb with OS Windows 7 installed - no RIAD - AHCI mode
Second HD Seagate 1Tb as data disk
i5 2500K - not overclocked
Everything is working fine, but a I try to install a new Radeon HD 6850 graphics card, the computer doen not start up at all.
I plugged it in the PCIEX16. When I unplug, the computer starts up normaly so it has something to do with this graphics card
Is this graphics card suitable for this MOBO
HD 6850 Card is PCI Express 2.1
TX

[DennisMenace]

I have a similar setup (UD3H/2500K) and have had no problems running a MSI 6870 Hawk.

There are a few options in BIOS/UEFI for disabling internal graphics when a GPU is detected, and which to use on boot and for the primary display, but these shouldn't stop the PC from booting. Does your PC complete POST (so you can access the BIOS options) or is it completely dead?

Assuming you have a decent ~500W+ PSU, and have connected the extra 6-pin power connectors to the GPU, it should work. Can you try the card in another PC, or try another card in your PC? Otherwise it sounds like a faulty card, or possibly the PCIE slot.