EVGA Options confusing!


macrumors member
Original poster
Nov 18, 2008
New Zealand
Hi, I am collecting parts to upgrade a Mac Pro 5,1
I have a choice of the following 2 GPU at the same price, I am a little confused with the 2 options in terms of power requirement differences and the ability to flash EFi firmware since these are different spec to the standard EVGA GTX 680.

EVGA GTX 680 Signature 2 OC
EVGA GTX 680 Superclocked

Which would be ideal and can be easily flashed to EFi firmware?


macrumors 6502a
Jul 10, 2009
Look at a picture of the physical card to see if it is 2x6-pin power or 1x6 and 1x8 power.

There is debate among the community on whether or not it's safe to simply use an adapter for 6 to 8, despite specification differences on how much power is drawn from a 8-pin vs a 6-pin. I personally think it's fine so long as your cards TDP is not egregiously above 250W given tolerances, but I am more willing to take risks and am not afraid to get dirty to fix a computer should something go wrong. If in doubt, play it safe and get a 2x6-pin.

Reference cards can usually be flashed with the 2GB ROM. There is now a 4GB ROM floating around. Just keep in mind if you flash, you may lose the factory overclocked settings without further modifications of your own. If you don't feel up to it, you might as well get a reference GTX 680 since you'll be running stock speeds anyways after flashing.


macrumors regular
Signature 2 card:
  • core clock 1098 Mhz
  • 2 fans
  • target power 200 watts
  • Max power 250 watts

Superclocked card:
  • core clock 1058 Mhz
  • 1 fan
  • target power 170 watts
  • Max power 225 watts

With respect to 8 pin power connectors: you will MOST LIKELY be fine with either of these cards, but you MAY be exceeding the power specifications of the built in PCIe supplimental power cables of the Mac Pro depending on the card and its physical design.

Cards with 8 pin connectors MAY be designed to draw up to 150 watts from that connector. The actual amount of power drawn from the connector is determined by the number of components wired to draw power from that connector. This is determined by the physical traces of the printed circuit board, and you cannot draw any conclusion between cards UNLESS you know they use the same board layout.

There should be no problem flashing either of these cards...
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