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I guess it makes sense right? 7970 x 4 ref fan speed at 55% Voltages at 925mv

Also how do I make it so I can copy and paste what's in the black box w/o taking a screenshot then uploading it online?

https://i.imgur.com/JeP8c.png

Whats the power draw at the socket? Kill-o-watt?

dunno haven't checked

That makes perfect sense. Bottom card doesn't have another card right in front of it's fan, so it has better airflow. Undervolting is always good: lower power, lower temps, and less stress on the VRMs. Stock ref coolers don't have as many issues with high VRM temps, so those cards should last you a long time.

If you're really concerned about the other 3 temps (tho high 50s - low 60s are great temps!), try adding a little spacer between each of the GPUs at the back corner, where the PCIe power plugs are, where the fans are. I bigger gap between the cards can improve airflow. It looks horrible, and I don't like this pic as it looks like you could damage your cards if you do it improperly, but here's what I mean:

https://en.bitcoin.it/w/images/en/thumb/f/f6/Quick-and-dirty-4x5970-cooling.jpg/800px-Quick-and-dirty-4x5970-cooling.jpg

If you're really anal, and you don't care about reselling the cards, you could always mod (http://hardforum.com/showthread.php?t=1683516) the PCI bracket. It only works with reference blower fans, but can make a difference (http://www.legitreviews.com/article/1355/2/).

Or you could just remove the bracket entirely.  But sometimes that logic doesn't apply here anyways.   ::)

A Dremel is a good investment in this situation.  The housing in many cases is not effective at guiding airflow where you want it when you are running a mining rig (i.e., with several cards next to each other in the open air).  Carve off the plastic housing, leaving enough in place to hold the fan steady and you should be able to achieve a 5+ºC drop at the same clock and fan speeds.  You'll improve convective dissipation both from the fan and the ambient airflow and reduce additive heat from the back of the next card.

Plus, Dremel!

This is NOT true for reference coolers. This is a BAD idea on your cards.

Stock coolers and their shrouds direct air from the back of the card (where the fan is), all the way across the heatsink, and out the back of the case, thru the PCI bracket vents. This is how it's supposed to work, and without that shroud, it will not work.

Non-ref coolers blow air from usually 1, 2, or 3 fans blowing down on a heatsink, not across a heatsink. In this scenario, removing the shroud could be beneficial.

It looks that way, but you may want to do a simple hand test with centrifugal fans.  They work by creating a lower pressure region along the axis.  Any "direction" you think you detect is based usually on the higher pressure between the shroud and ambient.

If you still want a bracket to hold the card in place without mangling your cards, just take one of the slot protectors that come with your case (or any case) and drill two holes for the hex spacers that the DVI cable screws into and then cut a hole for the connector.

When I modded my Anted 300 to fit my 5970s, I skipped the dremel in favor of tinsnips, because that's what I had. Totally worked, too. ;)

true DIY'ers Adapt and Overcome!!!

Those temps seem pretty damn good. My cards run at 65-70C with VRMs at 70-80C depending on shit in ambient.

I'm running mine at 1050MHz with VRMs at 1050mV in MSI AB, and 375MHz mem, but 90% fan. I get 615Mh/s, and when I left for work this morning, the core was at 48C. VRMs aroun 70s.  ;D ;D ;D

Oh come on! A lil electric tape to prevent any sharp edges from cutting up my PSU cables, and we're good!  ;)

You had to ask why? ::)   Common sense is so UNBELIEVABLY lacking.