How much 12v amp pulled from PCI-E slots ? (5830 vs 5870 vs 5970)

[Transisto]

Can someone with a precise DC clamp meter check the difference in 12v amp is pulled from the PCI-E slot of different cards.

The max PCI-e specification is 5.5 amp (66w)

The only data we have available are from WhitePixel 5970 @ 3.7 amp, 45w
(Numbers taken from powered pci-e extender.) http://blog.zorinaq.com/?e=42

How does this scale for dual GPU (6990) vs Single vs Lower end GPU (5870 vs 5770)

This is to figure out if people with 5-6 GPU per board need to use externally powered extender.

Thank You

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[likuidxd]

I can't help you with the figures you're requesting. I'm using 5870's, I would like to see someone go over the top of this build using 5970's or 6990's. I would like to know their results.

7-8 Single gpus work on one MSI Big Bang with no molex.
12 volt power cables from PSU are not hot or warm to the touch.

There is only one issue so far with running eight. Stability in the operating system.
Windows 7 will recognize 8 gpus with a lot of tweaks. ATI CCC can not be installed and I needed to build my rig up slowly after installation.
Linux Coin recognizes all 8 gpu's but from my experience lc has never been a completely stable platform.
Big A Miner Thing does not support 8 gpu's long term for some reason, but will support 7.
From Aaron Wolfe, creator of BAMT, when asked about the problem:

your best bet is to just pull the 8th card.

[DeathAndTaxes]

The max PCI-e specification is 5.5 amp (66w)
The only data we have available are from WhitePixel 5970 @ 3.7 amp, 45w

Interesting I have a differing value.  I did the same thing w/ 5970 on extender cable but it wa only ~30W. 

The only reason I can think of for a 50% difference is maybe WhitePixel is not downclocking the memory and thus increasing overall load and as a result the load on PCIe slot.  The 5970 in question was a second gen ATI reference card (the ones made by ATI but without the "handle").

I can grab my clamp meter and check a 6950 I still have (and maybe 6970).  If I get a chance I will do it this weekend.