Power connections between Intel DX58SO & Ultra X3 850 PSU

[niksimpson]

I'm building a system using an Intel DX58SO motherboard, Ultra X3 850 watt PSU and Saphire Radeon HD 3870 graphics card. There are a total of four possible power connections on the motherboard and one on the graphics card. Before I power the system up, I want to make sure that I've got the power connection correct...

From the PSU to the Motherbaord I have the 2x12-pin power connection, and the 2x4 PCIe power connection.
From the PSU to the graphics adapter I have the 2x6 pin connector on the graphics card connnected.

That leaves two additional connectors on the motherboard:

1. A 4-pin molex type connector (i.e. what you used to find on disk drives and the like)
2. A SATA style power connector (lableled "aux power" on the board)

The motherboard documentation is not clear about whether I need to connect these to the PSU for my configuration, nor is it clear about which output of the PSU they should be connected to (i.e. 5V, 12V etc). All the manual says is that one of these needs to be connected if I have a PCIe card that draws greater than 75 watts. Any help would be appreciated.

thanks.

 

[groo]

there should be a 24 pin main conector and a 4 or 8 pin aux 12volt cpu power conector on the motherboard. DO NOT plug the PCIe graphics card power conectors to the mobo. If you have a 4pin aux power, from the PSU, and not a 8pin, but the mobo wants an 8 pin, it may work with just the 4 pin, or you may need to get an adapter.
some PSUs make the PCIe and SATA conecotr black and leave the others white to make it simpler, but not all

is the molex conector the type you'd find on a FDD or an IDE drive. if it looks like the FDD type, its probably a 4 pin fan conector don't plug a live wire into it, only a fan. If its the IDE type, plug in a conector from the PSU

 

[niksimpson]

there should be a 24 pin main conector and a 4 or 8 pin aux 12volt cpu power conector on the motherboard. DO NOT plug the PCIe graphics card power conectors to the mobo. If you have a 4pin aux power, from the PSU, and not a 8pin, but the mobo wants an 8 pin, it may work with just the 4 pin, or you may need to get an adapter.
some PSUs make the PCIe and SATA conecotr black and leave the others white to make it simpler, but not all

I currently have the 24 pin main connector and the 8 pin aux connector from the motherboard connected to the power supply.

is the molex conector the type you'd find on a FDD or an IDE drive. if it looks like the FDD type, its probably a 4 pin fan conector don't plug a live wire into it, only a fan. If its the IDE type, plug in a conector from the PSU

The way the motherboard documentation reads, I only need this if I have a PCIe card that draws > 75watts, and I have choice between this connector or the "SATA style" power connector, but I should only use one of them.

 

[groo]

sounds like its for a card like the 4670, that doesn't have the PCIe conector and runs off PCIe board power, but draws near the PCIe limit standard.

I think your 3870 has a PCIe conector, use that.