I have a Fujitsu R940 YM9N model with a 1000W PSU and 2x GPU Power rails on it ( official Fujitsu cables with the 6 Pin and 8 Pin connectors on each one of the cables)
I Placed an EVGA FTW 670 on my PCIE x16 slot ( tried in CPU0 CPU1 and PCH Slots respectively)
All I get on power on is 3 long beeps after a while, dark screens no video ouput.
All fans running OK including the GPU-s one
in the rest of the computer all I have is 1 official 500 GB SATA 3 HDD and a Sound card Asus D2X which uses a floppy power connector from a converter of SATA power.
I have 2x Xeon E2603 v4 CPU-s
System boots fine with video output OK with the original Nvidia NVS 315 and my old Geforce GT 220 also ( none of those use extra 6 Pin power plugs for the record)
Thanks a lot