x1900xt and the 12v power connector

[youngkyun]

I decided to get a bigger PSU for my future 1900xt. I was wondering how you would connect the 2 12v's to get 30a on one 6 pin connector?

would i be using this?
http://www.newegg.com/Product/Product.asp?Item=N82E16812154001R

is that the correct connector? and is there a specific wire that is considered the "12v" connector? I am unfamilar with power supply wires. Thanks in advance.

 

[Vokofpolisiekar]

The link you gave returns with.... nothing.

You basically need a PSU, with two 12V rails. The 2 rails does not mean two physical 12V molex/pcix connectors. It just means that internally, the PSU can dedicate two 12v signals each with high amps. This is split into a.) CPU and b.) the rest of your system.

Seeing that amps wise, the gcard will consume much more than the rest of the system, it falls on this rail. The CPU requires a clean signal, and seeing that the PCIx x16 slot runs off the 12v from the connection to the mobo (hence the cpu - partially actually) it makes sense to let the other rail go to the mobo and cpu.

Rough guess:
CPU/Mobo 12v rail -> 80% CPU / 20% mobo
System 12v rail -> 80% Gcard / 20% system

In effect, the gcard gets it's power from both rails, but more from the system 12v rail.

To answer your question, the 1900xt will be fed externally through the PCIx power connection found on all ATX 2.x psu's. This 12v falls under the system 12v rail. Alternatively, there will be a connector with the gcard, that converts 12V via molex to pcix power connection.

 

[phreejak]

Take a look at this review of highend PSUs and how they function at idle and under load. It should aid you in finding somehting you are looking for.

http://www.bytesizedreviews.com/?rev_id=302

 

[youngkyun]

thanks for the replies, I guess what I'm trying to ask exactly is do I need to purchase a Y connector to connect two 4pin plugs into a single 6pin(?) plug? I plan on purchasing an Antec 550 PSU with two 12v 19a rails. does this psu come with 6pin(?) connectors to go straight into the x1900xt? or do I need to connect the two 12v rails with that Y connector? I am not sure how all the psu stuff works since I never had a video card that really required high power requirements. thanks.

 

[phreejak]

You're talking about a PCIe connector right?

 

[youngkyun]

well, I not sure what im talking about If I buy a x1900xt and an antec 550 PSU, will there be a special connector on the PSU to fully power that vid card ? or would I have to get some kind of Y connector to connect two 4 pin connectors?

sorry if this if my questions arent very clear, I'm having a hard time conceptualizing how a PSU works with volts and connectors and what not.

 

[phreejak]

Current PSUs have dedicated PCIe power connectors specifically for graphics cards that require them and the Antec 550 comes with 2 of them. That PSU is also SLI certified by Nvidia

 

[Vokofpolisiekar]

Yes, if it's a Antec TruPower 2 - it will have a six pin PCIx power connector. The gcard will ship with a y connector, with two 4pins molex going to the 6 pin - but it's not to power two 12v into the 6 pin, the one molex (4pin) is male and the other female, so it allows you to power from the psu to the 4pin, which then goes to the 6pin pcix, and then from the last 4pin you can connect a hdd/cdrom/fan etc (series connection).

 

[youngkyun]

so just plug one of the pcix power connectors to the x1900xt and it will be good to go with enough power?

 

[Vokofpolisiekar]

Yup - if the PSU has a six pin PCIx connector then connect it.

If the psu only has 4pin molex's, connect that to the y-adapter (2x4pin molex into 6pin connector) and then connect the 6pin to the graphics card

4pin male 4pin female (from PSU 4pin male into this one)
\/
|
6pin PCIx (graphics card)

 

[phreejak]

For higher end setups like xtx crossfire or 7900 gtx sli setups and configurations of that sort, newer motherboards provide for more power stability by adding a 4 pin molex connector directly ON the motherboard (in addition to the 4-6 or 8 pin power connector and the 20 or 24 pin power connector boards normally have).

 

[youngkyun]

thanks, you guys have been a great help!