Hi All 
I have a brand new system I put together yesterday. The components of interest here, are the mobo ASUS X99-E WS and the Corsair Vengance CMK16GX4M4A2133C13 RAM kit.
X99-E WS has 8 ram slots, 4 black and 4 grey slots. I initially decided to use the black slots, but when everything was set and done, and I turned the system on for the first time, it didn't boot.
The Q code indicator displayed code 53, the same code it displays wheb there is no memory installed at all.
Then I switched to the grey slots and the system booted just fine. I tested the system with three RAM modules installed on grey slots and one on a black slot, and it booted but without detecting the RAM module that was installed on the black slot.
I was really worried initially that my mobo is faulty, but then I realized that I have not connected one of the two 8-pin power connectors the mobo has; Now X99-E WS has three additional power connectors besides the main 24-pin one. There are two 8-pin connectors at the top of the board and on 6-pin connector just above the top-most PCI-E slot.
I see a mobo with multiple 8-pin power connectors for the first time and I didn't know what to do with the extra two power connectors (8-pin and 6-pin), and I couldn't find any information about them in the manual, besides: "Those are power connectors" .
So I googled and found a video describin a building of a PC with an X99-E WS and saw that only one 8-pin connector was connected (the CPU power) and the other two left empty, so I decided to do the same... The build I watched had 4 RAM modules installed on the grey slots...
Is it possible that one of the two extra connectors powers the the RAM installed on the black RAM slots? Because the system really behaves like nothing is installed on those slots. And if not, what are they for anyway? Obviously the system can work without them, so in what cases they have to be connected?
I am worried. I don't want to experiment randomly connecting power cables, so can someone please confirm that I have to connect the other 8-pin connector to the PSU to get the black slots operational or what's the actual problem...
Thanks a lot, in advance!
Update: I connected all two additional power connectors to the power supply. But there was no effect at all, RAM modules on black slots are still not detected, at this point I think mt mobo is defective and I need to RMA.

I have a brand new system I put together yesterday. The components of interest here, are the mobo ASUS X99-E WS and the Corsair Vengance CMK16GX4M4A2133C13 RAM kit.
X99-E WS has 8 ram slots, 4 black and 4 grey slots. I initially decided to use the black slots, but when everything was set and done, and I turned the system on for the first time, it didn't boot.
The Q code indicator displayed code 53, the same code it displays wheb there is no memory installed at all.
Then I switched to the grey slots and the system booted just fine. I tested the system with three RAM modules installed on grey slots and one on a black slot, and it booted but without detecting the RAM module that was installed on the black slot.
I was really worried initially that my mobo is faulty, but then I realized that I have not connected one of the two 8-pin power connectors the mobo has; Now X99-E WS has three additional power connectors besides the main 24-pin one. There are two 8-pin connectors at the top of the board and on 6-pin connector just above the top-most PCI-E slot.
I see a mobo with multiple 8-pin power connectors for the first time and I didn't know what to do with the extra two power connectors (8-pin and 6-pin), and I couldn't find any information about them in the manual, besides: "Those are power connectors" .
So I googled and found a video describin a building of a PC with an X99-E WS and saw that only one 8-pin connector was connected (the CPU power) and the other two left empty, so I decided to do the same... The build I watched had 4 RAM modules installed on the grey slots...
Is it possible that one of the two extra connectors powers the the RAM installed on the black RAM slots? Because the system really behaves like nothing is installed on those slots. And if not, what are they for anyway? Obviously the system can work without them, so in what cases they have to be connected?
I am worried. I don't want to experiment randomly connecting power cables, so can someone please confirm that I have to connect the other 8-pin connector to the PSU to get the black slots operational or what's the actual problem...
Thanks a lot, in advance!

Update: I connected all two additional power connectors to the power supply. But there was no effect at all, RAM modules on black slots are still not detected, at this point I think mt mobo is defective and I need to RMA.