Galax Geforce 970 SLI and NZXT Kraken G10

varkanoid · 14 Jan 2015 at 16:25

Just thought I would share my experience with fitting the NZXT Kraken G10 to a GTX 970. I wanted to go SLI for the first time. I had a GTX 970 MSI card and sold it then bought two Galax GTX 970 with Blower cooler (http://www.galax.net/europe/970v.html)as I read that these type were better for going SLI. Not sure whether this was a good decision. I thought it was best as I intended to watercool.

First the noise. As the top card was always the hotter one the fan did tend to spin a bit noisly during gaming/benchmarking. It would go 75c to 81c depending on what I was doing. The bottom card was doing 61-65c.

When I had enough spare cash I looked into watercooling and it was coming in at £275-£300 to do maybe a bit more if I included a CPU block. Then I hit snags. Only double rad I could fit in my case was the Ice Stealth as it was thin enough. Then I found out EK and XSPC do not sell full cover blocks for these cards. So my alternative was a GPU only block and cool the VRM/RAM seperately which I didnt want with a full watercooling kit.

So I then looked at the NZXT Kraken G10 and at the prices of AIO liquid coolers. I picked up a H55 refurb for the bottom one and a NZXT Kraken X41 for the top card due to the limited places I could mount them. I also bought some RAM chips for the RAM.

I took the cooler off the first card to reveal a whacking great big VRM heatsink and also no direct RAM cooling at all. Bit surprised. Then I realised the G10's were intended for full length PCB's. Bit of a snag. So I fitted it anyway but never bothered with the 92mm fan as it wasnt really cooling anything other than pushing air round my case. So I fitted them all in and added a 120mm fan blowing directly onto both VRM Heatsinks to aid cooling.

Did some gaming and benchmark tests and the top card does 49-51c and the bottom card does 41-45c which is a great improvement. Also the X41 you can use their CAM software so not only does it give you GPU and CPU temps but it tells you the temp of the liquid going round the X41 which is pretty neat.

Anyway few pics below. Some people might think it was a bit mad but quite happy with it so far. Cost about £150

One fitted

Two fitted

pastymuncher · 14 Jan 2015 at 16:57

What are the vrm temps like now that they have no direct airflow? The reason the blower coolers are best for SLI is because they exhaust the air out the rear of the case. You didn't need blower versions as you took the coolers off.

varkanoid · 14 Jan 2015 at 18:28

pastymuncher said:
What are the vrm temps like now that they have no direct airflow?

Not sure as I am trying to find a program that measures it. It doesnt show in the pic but there is a 120mm fan blowing air onto both VRM's.

pastymuncher said:
The reason the blower coolers are best for SLI is because they exhaust the air out the rear of the case. You didn't need blower versions as you took the coolers off.

I know that was the reason. I bought them as they were the cheapest 970's at the time and if I was happy with the temps etc I would have kept them as is.

pastymuncher · 14 Jan 2015 at 18:51

GPU-z shows vrm temps.

varkanoid · 14 Jan 2015 at 21:55

Not with my 970. I have been reading up and some GTX 970's do not show the VRM temps.

pastymuncher · 15 Jan 2015 at 10:46

That's dissappointing. That's actually pretty sparse on monitoring sensors for a modern card. Does Galax have any software of it's own that may show it?

varkanoid · 15 Jan 2015 at 11:50

Yeah they do its called XTREME TUNER PLUS

Looks a bit like a custom gui afterburner. Will give that a try.

hugobosslives · 15 Jan 2015 at 16:22

surely you want the radiators swapped over?

you've got the bottom card getting the cold intake air, whereas the top card is using already hot air from both the cpu and other gpu. the top card will normally work slightly harder so gets hotter anyway

varkanoid · 15 Jan 2015 at 20:52

The tubes on the top radiator wont sit right with the card in the bottom slot. Thats the limitation. You can angle them from the pump to the left but the tubes end up sticking out of the side of the case. If you angle them to the right they dont reach the top fan mount. The front radiator works with the card in both slots. The top radiator is probably 1.5 to 2x as big as the front one so that should compensate a little.

It does as the gap between them is about 10c now when it was 15-20c before. I had tried different combinations and this seemed to be the best compromise.

Problem with AIO liquid coolers is the pipes can be small. The corsair ones are 30mm. The NZXT ones are 40mm. The Antec ones are also quite long too.

JustCallMeVlad · 15 Jan 2015 at 21:03

I would zip tie a pair of fans to blow on the VRMs

varkanoid · 15 Jan 2015 at 21:32

I have a 120mm fan running at 1300rpm blowing straight at the VRM's. Its not in the picture. I might be able to put a thin 80mm fan on both of them but not sure whether its worth the hassle. The temp probe from my fan controller sat in between the fins of the bottom VRM measured 91c after running Heaven benchmark and the top one measured 99c after a second run of Heaven. Not sure how accurate it is but gives a good indication.

pastymuncher · 16 Jan 2015 at 09:44

Ouch, that's damn hot. The chips themselves will be even hotter. With a 200mm side fan fitted to my case running at a silent 500rpm and a copper heatsink I made out of a 1u server cooler sitting on my 780's vrm's, the heatsink is in the low 50's while gaming according to my fan controllers temp probe and backed up by a IR temp gun. I think you need to get some decent airflow over them.

AndrewUK1990 · 16 Jan 2015 at 10:22

AFAIK the 980 water blocks fit the 970 and they are full cover blocks. Also, although the 970 blocks are shorter they are still classed as full cover blocks if you go on the EK website. TBH though the 970 even clocked off its nut doesn't need water cooling if the air cooler is half decent. My MSI 970 hits 72c max in benching and its at 1.26v @ 1550mhz core 8000mhz vram.

varkanoid · 16 Jan 2015 at 11:43

AndrewUK1990 said:
AFAIK the 980 water blocks fit the 970 and they are full cover blocks. Also, although the 970 blocks are shorter they are still classed as full cover blocks if you go on the EK website. TBH though the 970 even clocked off its nut doesn't need water cooling if the air cooler is half decent. My MSI 970 hits 72c max in benching and its at 1.26v @ 1550mhz core 8000mhz vram.

I contacted EK and XSPC direct and they told me the only waterblocks that fit my particular card are GPU ones. I sent them a picture of the card and there is something about the layout of the Galax one that means full covers dont fit. You need to think about better cooling if going SLI.

pastymuncher said:
Ouch, that's damn hot. The chips themselves will be even hotter. With a 200mm side fan fitted to my case running at a silent 500rpm and a copper heatsink I made out of a 1u server cooler sitting on my 780's vrm's, the heatsink is in the low 50's while gaming according to my fan controllers temp probe and backed up by a IR temp gun. I think you need to get some decent airflow over them.

Not really as VRM's are designed to run hot. I think I read that they are rated upto 125c. It wasnt a very scientific test anyway. I think my Dad has some heat temp equipment I might borrow.