We have a Dell Precision Tower 3620 and have purchased a firepro W7000 to install. only problem is the 6 Pin connector provided by dell has a different pin arrangement. the middle top pin as you look at the plug is square instead of the usual rounded corner pin so will not go into the socket.
The only video cards validated in the Precision T3620 did not need the power supply lead. So this may be why the 290w PSU is lacking the correct cable? Perhaps another Precision T3620 can open their case and also check the PSU cabling.
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