Well, it was an enjoyable Memorial Day weekend with some good food, hanging with the fam, and some solid modding and testing time.  I tackled a near complete tear-down and rebuild in order to remove everything from my 800D case so the top could be safely cut open to support a Bitspower 4x120 radguard and an upgrade from a Feser 360 to Feser 480 rad.  I already posted a couple of small pics in the "prelim build pics" thread so no need to post them here.  This is just a short post to point out that the upgrade to a quad radiator lowered peak GPU temps by about 5-6C when folding or in heavy benching. 

On the triple rad they were about 57C for the first GPU in the loop and 58C for the second GPU in the loop.  This is a 100% serial loop ordered like:
Swiftech 655 -> GPU1 -> GPU2 -> CPU -> NB -> VREG -> RAD.

Now with the quad rad they are loading at 51-52C.  The room is a couple of degrees warmer than usual for my benching/testing so the numbers might even be a little better than that, but I figured I'd just be conservative.

It was a ton of work to upgrade just an extra 120mm but the point was to really understand how radiator sizing will affect these GPUs with all other things equal.

Oh, both cards are overclocked to 850/2000 at the moment so they do run a little bit warmer than they would at stock.  At stock I suspect they'd load in the high 40s but I have yet to test.

Hope this info helps when others are sizing their loops and systems.  I'm definitely happy with the extra headroom because it seems like crazy things start happening when either GPU hits about 60C on more aggressive overclocks (875+MHz).  For anything short of aggressive overclocking I think a triple rad will do most people fine.

nice report thx 

I would really consider adding a couple of splitters to that loop setup to decrease the temps on your CPU/NB/Vreg and possibly even a degree or two drop in your GPU's.

luv2increase

Thanks for sharing!!!  Have you tried to go higher than 850/2000 yet?  It seems like you have a lot of room left now :)

My pleasure...  I might eventually start hanging radiators somewhere outside of the chassis for benching but I'd really like to see how far things can go without doing that first.

I did push the cards up to 900MHz with OC Scanner but haven't successfully benched them at that frequency.  Maybe tomorrow's the day? :)

Nice post.  I have also been thinking about going to a 480 Rad.  My 120.3 seems to be keeping the cards at a very respectable temp range of 33C idle and 50C full load. I am worried once I am able to start overclocking them I will not be as happy with the results though.  I just have not had time to mess around with overclocking them as my Phase Change unit busted during the instillation of the graphics cards and I have been busy repairing that.  I have some Scythe UK3's I was going to throw on my Rad first but now I am thinking a HWLabs GTX480 with Scythe UK3's might be the better option.  Your 6C difference lead's me to believe I should see similar results. Thanks for the information very helpful...

Very cool, I'm glad the data was useful to a few of you! 

I started looking around tonight to see if there was a single 120mm that would fit nicely at the back of my case and noticed that Frozencpu has a ridiculous Feser 480 deal going on right now.  I guess they are blowing them out since Feser discontinued their rads.  I really don't need any extra radiators lying around but at $99 for a quad Feser...  man, kinda hard not to think about it. 

Well the scythes get loud above 2k and I'm running 7 of them on 2 rads so I keep them around 1.6k rpm.  I'm totally sold on the feser rads and only wish that sale had been on when I bought my quad.

HRPuffnstuff

Well the scythes get loud above 2k and I'm running 7 of them on 2 rads so I keep them around 1.6k rpm.  I'm totally sold on the feser rads and only wish that sale had been on when I bought my quad.

I also have a Phase Change Unit so I barely hear my fans over the compressor.  That is why I say noise isn't really a factor per say because it takes quite a bit of noise to overcome the sound of the compressor.  I know I couldn't live with a bunch of Delta's screaming at 3000 RPM but other than that the Scythe UK3's don't bother me to much. Especially when I have my headphones on I can't hear a thing.  My wife regularly walks in and taps me on the shoulder and makes me poo my pants...LOL  Right now money being no option I just want the best 480 RAD I can get but it seems it is really hard to get a straight answer on that.  A few years ago everyone would just say Thermochill is tops hands down but now it seems just about every company has a top notch high quality Rad.  I guess no matter what I pick I probably can't go wrong whether it be an XSPC, HWLabs or Feser. I do plan on using Med-High speed fans so I just want to know which works best with that type of fan setup.

hombredelassrtas

nice info. Any thoughts on how a double 120 rad will work with a single gpu only on the entire loop? i just finished putting mine together. Today i'm adding water and letting it run 24hour before putting it back in the case. Curious though how it will work out

You should be good if it's a decent radiator... before I was running my dual 480s + CPU + mobo on just a triple. 

Cool CREUSS, enjoy the new Feser 480 when ya get it.  I am enjoying mine without question! 

Right now I'm using the Bitspower rad guard.  I think I got it from Sidewinder since PPCS was out of stock :(

I think you are correct in your concern though.  The Bitspower acrylic fan grill portion appears restrictive for anything more than low speed fans, and if it was sucking air in could easily get stuffed with dust and fur if you have pets.  I will be removing my acrylic grills tomorrow, time permitting, to see how performance is impacted. 

BTW, MNPCTech makes some niiiice stuff.  It's too bad they didn't seem to make a 480 like you said or I would have maybe gone with them.  In particular I like how thick their rad guards are, the Bitspower one is a little flimsy imho.  It's fine when mounted as rigidity comes from the case and the rad itself.

^^^^^^^ Man, I looked all over their site for a 480 rad grill and didn't see it.  Now I see the mnpctech.com lettering on the picture you posted above and should have noticed that before.  Oh well. 

Keep us posted on your setup..