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dual 12v rail, good or bad for high end video card?

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"Minimum of [email protected] for Single Video Card Systems & [email protected] for Dual Video Card (SLI) Systems. "

 

I saw that in the PSU thread.. mine has two 12v 19 amp rails. Could this be the reason behind my video card struggles, even when running at stock or below stock speeds on every component?

 

Since it seems it'll be a long, long time before I get any RMA out of Sapphire's outsourced company for RMAs, I might as well make 100% sure it's not anything in this computer first.

 

The other graphics card I tested to ensure it was thids graphics card causing the problem was a passively cooled x300se.. didn't exactly strain the PSU at all.

 

My problem is artifacting when going into the BIOS and not being able to go into linux at all, which happened before I unlocked the pipes so I know something had to be up before I began screwing with it.

 

If I were to try say the OCZ powerstream 520(the only alternative PSU I have tried was a 500w dynex with very similar ratings to my current PSU, with the same problem), could this possibly solve my problem?

 

It plays games but has issues merely going into the BIOS and booting into linux without freezing or giving battery errors..

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The problem is to divide the load between the two rails. If PSU has 6 pin SLI leads, this should be simple. If you are using Molex to 6 pin extensions, just use different PSU leads.

I have seen a lot of problems recently with the Antec Truepower 2.0 550 in the sig. You may have to use DMM to check load conditions. If you get both 7800's on the same rail then that could be problem.

All I can offer. Good luck.

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As you have surmised, there is not enough power on a single rail so you have to divide between them. I would put the X850 on a rail by itself and other things on other rail, but that is up to you on dividing the load.

Good luck.

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I haven't seen an X800 so I don't know if they have a PCI-Express power connector or a Molex for the additional power.

 

A PCI-Express power connector incorporates both 12V rails and a properly designed card should pull more or less evenly from both rails. A standard Molex connector only uses 1 rail and this would cause problems.

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Antec Truepower 2.0 550
This is more that enough.

 

On dual rail PSU's, one rail powers the CPU via the p4 connector &

the other rail powers everything else, including the video card(s).

 

A "max combined" rating of [email protected] is fine.

 

Are all of the power connectors plugged in?

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Yeah, they all are.

 

With RMA processing fees and shipping that costs me $30 for a mere RMA of the card, I wanted to make sure it was the card at fault.

 

The card uses the 6 pin PCI-E connector.

 

Thanks for all the help.

 

The DAGF only has the 24 pin power and the 4 pin power.. plus the 6 pin on the graphics card, which is plugged in.

 

I guess it is the card. I will send it back, and if the next one doesn't work and sapphire expects another $30 to RMA it, they can eat my butt. :|

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The Antec 550's are pretty stout. I have a True Control 2.0 powering the rig in my sig and the voltages fluctuate less than 0.5% under load.

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A Y connector will take 1 connector in and give you 2 out with varrying configs for each end...

 

usually a Female 4 pin molex (or HDD type) to 2X 4 pin molex or 2X floppy type,

or 4 pin molex to a molex and a floppy type (just the thing for a tidy install on DFI NF4 Boards, if only i could find a pretty silver braided UV one to match my modsteam PSU :) )

 

latley dual molex two single PCI-E connector ones are appearing but are only worth while if you feed each molex from a sperate rail

 

oh ya... they make a great point of often overlooked failure :nod:

 

Do a google image search on "Molex Y cable" for some pics :)

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