i bought 3 of these off your ebay, magicgrow...etc etc. i can't seem to get them to work, tried all 3. i plugged in molex, molex is attached to hard drive and psu. gpu isn't recognized in device manager. if i directly hook up gpu to mobo, it works. when i attach to your cable/card, gpu isn't recognized. help!
corsair 1200ax
12gb ddr3
amd fx 4400
2 @ xfx r9 270x
1@ xfx r9 290
asrock extreme 4 970 mobo
First make sure they work without the risers. Put the cards in right on the motherboard. If they're still not showing up, your cards and/or motherboard and/or OS setup are hosed. If at any point you have reversed the risers, you have likely fried things. If they work, then move on:
Second, sometimes windows has issues using GPUs which are only on the 1x pcie format, especially AMD-based ones. Reboot several times, they might start showing up one at a time. I've seen that solve it.
Third, don't use windows to mine, try an alternate setup. Try BAMT, for example.