6990 rig setup help (b)

[Sjalq]

I have a 1200W CoolerMaster gold. This thing emits enough power to run support hardware and 3x6990s (Club 3Ds). Problem is the cables do not match with the graphics hardware PCI-e connectors. The PSU has 4xPCI-e 6+2 connectors and 2xPCI-e 6 connectors. The cards have 2xPCI-e 6+2 connectors each. So now I can power 2 cards, but not the 3rd one...

Does anyone know whether the cards can run on one PCI-e 6+2 connector and one PCI-e 6 connector like normal cards seem to?

[kloinko1n]

This thing emits enough power to run support hardware and 3x6990s (Club 3Ds).

I dare to disagree with you on that.
Or, at least I have some serious doubts.

[allinvain]

Use a molex to 8 pin adapter or a 8 pin to 6 pin converter and a molex to 8 pin..

[NetTecture]

This thing emits enough power to run support hardware and 3x6990s (Club 3Ds).

I dare to disagree with you on that.
Or, at least I have some serious doubts.

He does what I do.... try to mimic the 3x6990 setup from https://en.bitcoin.it/wiki/Mining_rig#Three_ATI_6990s,_Approximately_2.1_Ghash/s

It says 1200w And 3x6990

[Maxxx]

This thing emits enough power to run support hardware and 3x6990s (Club 3Ds).

I dare to disagree with you on that.
Or, at least I have some serious doubts.

He does what I do.... try to mimic the 3x6990 setup from https://en.bitcoin.it/wiki/Mining_rig#Three_ATI_6990s,_Approximately_2.1_Ghash/s

It says 1200w And 3x6990

Have you got yours running yet or still ordering?

[NetTecture]

This thing emits enough power to run support hardware and 3x6990s (Club 3Ds).

I dare to disagree with you on that.
Or, at least I have some serious doubts.

He does what I do.... try to mimic the 3x6990 setup from https://en.bitcoin.it/wiki/Mining_rig#Three_ATI_6990s,_Approximately_2.1_Ghash/s

It says 1200w And 3x6990

Have you got yours running yet or still ordering?

Currently getting quotes and asking wild here - if I get the stuff sorted out, I would order next week, put it in poduction after the following weekend (because I bet some parts do not arrive till end of the week). Would be 1 of x

[Sjalq]

Well I am learning a lot. Feels like I'm 14 again

I also have my doubts if the power supply will supply a 3rd card now, but we'll test and see, maybe have them all under-perform until we can source more juice.

Great fun this mining business!

[NetTecture]

Actually it should. Going through some other posts it looks like people get the cards down quite a lot pwoer wise by selectively tuning the frequencies.

Moving memory to 300mhz seems to be recommended with people saying cards run around 65 degree centigradem, and IIRC i read somewhere someone said fans at 30% - this indicates the card may run hot on a point (the processors) but memory and shader units are not busy at all... which makes sense

[bcpokey]

Even without downclocking memory a 1200W is enough to power 3x 6990s, though it is pushing the envelope a little bit. 6990s use ~375Watts per card (300 from 2x 8pin and 75 from PCI-E slot). That's 1125Watts max to be within ATX specifications. In reality they pull less but anyway I digress.

To power 3 6990s you will have to get an 8-pin adapter cable. 8Pin PCIE cables supply 150Watts, 6Pin 75, so do not simply try to plug a 6 pin into the 8pin socket. There are 2 extra ground cables iirc in the 8pin.