Quote from: Eldoen on April 20, 2014, 08:08:00 AM

Power[edit]
All sizes of ×4 and ×8 PCI Express cards are allowed a maximum power consumption of 25 W. All ×1 cards are initially 10 W; full-height cards may configure themselves as 'high-power' to reach 25 W, while half-height ×1 cards are fixed at 10 W. All sizes of ×16 cards are initially 25 W; like ×1 cards, half-height cards are limited to this number while full-height cards may increase their power after configuration. They can use up to 75 W (3.3 V/3 A + 12 V/5.5 A), though the specification demands that the higher-power configuration be used for graphics cards only, while cards of other purposes are to remain at 25 W.[9][10] Optional connectors add 75 W (6-pin) or 150 W (8-pin) power for up to 300 W total (2×75 W + 1×150 W). Some cards are using two 8-pin connectors, but this has not been standardized yet, therefore such cards must not carry the official PCI-Express logo. This configuration would allow 375 W total (1×75 W + 2×150 W) and will likely be standardized by PCI-SIG with the PCI-Express 4.0 standard. The 8-pin PCI-Express connector could be mistaken with the EPS12V connector, which is mainly used for powering SMP and multi-core systems.

there is the Power spec's per Wikipedia. so the Slot itself offers up half of the power. and then the connectors offer the additional power needed by the card.

El

Yeh I forgot about the Actual Slot itself So with the Slot itself this is 300w Total, for a 290x Still though there must be quite abit of le-way available because these cards are great overclockers and even encouraged to be overclocked so stock @ 300w when they are running at 100% And the manufacturers allow some Overclocking meaning it will go over the standard 300w that the company states as being standard, I mean the companies create software to overclock the 290x, And all that is requited is 1 x 6pin & 1 x 8 Pin and of course the 75 watt Motherboard slot that you stated. Which makes me think, I really Doubt a company will create a card that reaches the PCI-E connectors ABSOLUTE limit as-well as the Motherboard slots ABSOLUTE limit. I have overclocked my cards witch went over and beyond the 300w limit and in fact I have some right this moment running in my 1200w With Powertune 20%+ and Memory clocked over the standard all day every day.... I am going to do some research on this because it does not seem right being 75w & 150w and then 75w from the slot when the card can go over the 300w.

EDIT:: OK guys I did some research and found a thread that had a few people wondering also and someone who ended up doing the research found the following Bellow-

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"Dear Johnny & the group,

Have learned several interesting facts about the PCI-E plugs and power after researching it this past week, that is worth sharing

The PCI-E connecter that has 6 pins. They are not all used for power. For the 6 pin connector, Pins 1 & 3 are 12V & each can carry 8 Amps. Pin 2 by spec is not connected, although some PSU manufacturers do add a 12V line there. Pins 4 & 6 are Com return lines. Pin5 is Com for sensing. Using 2 lines, you get 12V*8A*2= 192Watts, much over the required 75Watts.

With an 8 pin PCI-E connector, 2 Com lines are added (4&Cool not a 12V & Com. There, Pins 1,2,3 are 12V, Pin 4 is a Com for the 8 pin connector sensing, Pin 5,7,8 are Com return lines, & pin 6 is for the 6 pin connector sensing. Using that config, 12V*8Amp*3=288 Watts, much over the required 150Watts.

Since Mar 2005, the molex pins are required to be "HCS" rather than "Std", which each carry a max of 11Amps. So properly made, an 8 pin PCI-e can supply 12V*11Amps*3lines=396Watts of power for the graphic cards.

Ther aren't 4 12V pins on the 8 pin connector, only 3, and 2 leads are used for sensing the connector type.

The other limiting factor of course is the width of the PCB lines on the graphics card, each typically carrying 1-2 Amps. That would also determine how much power it could carry to the graphics electronics.
Also worth noting Scott Meuller in his latest 19th Ed of "Upgrading and Repairing PCs" has this information incorrectly listed.

Hope that answers most of the questions regarding this unusually engineered connector."

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Interesting ay, now that makes a little more sense to me if thats the case , like I said I really doubt AMD will create a card using the ABSOLUTE connector and MB limit, this is ridiculous and will be frying PCIE connectors MB slots all over the place