Quote from: shat on May 18, 2011, 05:02:12 AM

I can go caseless on a shelf/tray in a rack. We have ~ 15 racks, not too much free space, but enough to get by. Currently, I just tried plugging in a 5850 using those silly molex 4 to pci-6 pin connectors that ship with the units... the video card gets power, the fan is spinning... but it doesn't show up in windows.

Not sure why, I tried multiple cards with multiple little adapter cables. I was hoping to use some of these smaller 650W psu's i have laying.

damnit... ideas?

So you tried how many cards at once with the molex to 6 pin pcie connectors? It may mean the PSU ran out of juice on the 12V rail or it's not able to keep up the voltage due to load.

You can use 650 W PSU but for no more than 3. I run 2 5870s off of a 600W PSU and it holds up just fine but doesn't have that much more room for expasion (438 Watts at full load) and I too also use those stupid molex to 6 pin PCIe cables - wish I didn't have to but I'd have to get another power supply then (what I'm using is a left-over I guess from an older desktop of mine)

Did you also try connecting the monitor directly to that card (the one powered by the molex connectors)? If you're not running in crossfire mode windows will shut off whatever vid card is not connected to a video load (monitor) so if that's the case then you're going to need some VGA dummy cables.