Quote from: justin399 on February 18, 2014, 01:11:05 PM

Well let me first start off by saying im very new to this, a month ago i wouldn't have known the difference from a gpu to a cpu. needless to say i think ive come far along, built my first working rig, gained alot of knowledge and am impressed with myself to say the least. my system is open frame, gigabyte 990 fxa ud7, seasonic 1250w gold, fx 6300processor, and 3 msi r9 280x gaming gpus (s/n starting in 38). anyway ive been mining for about 2 weeks with just 2 gpus because of very hot temps. usually 80-90c on gpu 0 and 75-80c gpu1. Finally got 3 riser cables after waiting for weeks and tried setting them up to get the 3rd gpu running. After trying again and again i cant seem to get cables working. ive tried all 3 cables on different cards and in different slots. when i pull out cables and set gpus on mobo they read fine minus the heat. but when i attach riser cable i get nothing. checking device manager shows nothing but the single gpu i have on mobo. tho when i have riser on gpu, fan is on and seems like its running. ive also tried plugging in monitor to gpu on riser with no luck. tried only using riser with gpu and nothing on mobo, again no luck, no boot screen, just black. cables i have are 16 x 16 un powered 16x16 powered and 1x 16 powered. i have not tried powering the cables yet as the most ive run so far is 2 gpus.

Also ive heard that an update to the r9 280x bios fixes heating problem but as im still messing with cables that seems like a whole other headace to deal with Undecided

not sure if thatd help or if i have the right version of r9s for the updated bios so i could eliminate the cables but would still like to raise the cards for better air circulation. any help is much appreciated.

I think I had a similar problem when attaching a 3rd gpu after I had everything installed and setup in windows. It wouldnt see my extra gpu either. All I had to do was do a clean uninstall/reinstall of the video drivers and all worked fine after that.