I7-7700K w. H100i V2 Average Temperatures

Hello all!

First off, this is not a "is something broke" post as there is great information here on the forum to resolve most issues.

My post is more for curiosity, I'm new to water cooling and AIO setups, as I've used air cooling for prior builds up until recently.

I know the I7-7700k runs hot by default, as Intel states operating temperature up to 80*C is "safe" (however, hot!). I also understand that coolant temperature can essentially only be as "cool" as ambient temperature in the room and/or case (depending on how you have your radiator configured). My average idling temperature is about 31-34*C.

For example, when playing games like Doom, I see my CPU package temperature in Corsair Link hit around 55*C to 60*C on maximum settings, with the H100i v2 registering around 38*C in a room that's about 27*C. Next, playing Rise of the Tomb Raider, I see roughly 45*C, H100i v2 about 38*C (of course, extended play heat soaks the fluid). Both of which are running in the default "Balanced" profile.

Attached is screenshots while playing ROTTR, for roughly 30 minutes by the time I took the screenshot, playing it for about an hour only increases the temperature slightly on the H100i v2 (I think I saw a peak of 39*C). My apologies as I don't have any screenshots of Doom to compare with at this time.

That all said, here lies my question as I'm more curious of efficiency. When should one be worried and when not to be worried temperature wise on the fluid side of things.

Also attached is photos of my rig with how things are configured in the case, does anyone have any recommendations of what "should" or should not be done?

Thanks in advance, looking forward to reading feedback!

Thanks for the info! This is good stuff!

I just wanted to compliment you on your build and noticed you had purchased the DemciFlex filters. I would highly recommend that you turn the rear fan around as an intake and place a filter on there. This will improve your cooling as you'd be in positive pressure. I always recommend positive pressure in all builds, having more intakes than exhausts.

Thanks for the info! This is good stuff!

 

I just wanted to compliment you on your build and noticed you had purchased the DemciFlex filters. I would highly recommend that you turn the rear fan around as an intake and place a filter on there. This will improve your cooling as you'd be in positive pressure. I always recommend positive pressure in all builds, having more intakes than exhausts.

Thank you! I was unsure on what to do with the rear fan filter, seemed silly to stick it on when the fan is blowing out, I will flip it and add the screen on there. I've always been curious on positive vs negative air pressure in a case, you hear so many ups and downs to both sides, its frustrating and intriguing all at the same time!

I'm also really impressed with the DemciFlex filters as well, I have miniature Australian Shepherds (think full size ones in 15 lb and 25 Lb packages, ha!) and there is hair everywhere. About a month into running the rig I noticed hair coming up from the bottom near the hard drives, so that led me to find a filter for the bottom and ultimately buying the entire kit. Definitely NOT a design flaw on the case by any means, its totally an environmental thing for my house, ha ha!

So, are you asking how much coolant temp rise (H100i v2 Temp) you should expect?

I am going to proceed on that assumption for now. If you idle coolant temp is around 31-32 and the room temp is 27C, that is about as good as you can do. +4-7C is the number I usually quote, although that is very case and environment dependent. Specifically in a 540, I could get it down to 2-3C with normal radiator fan levels, but that was an experiment in what is possible and not really reflective of a normal set-up. So the initial set-up and functionality seems fine.

I guess what you are really wondering about is the wide range of coolant deltas between the games. You also included some GPU and graphic settings which makes me think you know where the heat is coming from. Only small amounts of that heat is CPU related and overwhelming majority is GPU waste heat that has raised the ambient temperature of the case and the cooling system as well. In your Link shot, the 960 Pro is reading 40C. I can't get mine to hit 40C except by transferring 100GB and turning the fan off. Your m.2 is in the same place as mine and we have similar watt GPUs. The only time my 960 will reach 33C is when the case is also 33C. That has been true in a 540 and a 740. Furthermore, playing TR in DX12 keeps your CPU core temps very low. Mine don't even break 40C. However, that is your warmest coolant levels. Not coincidentally that is most taxing GPU game, especially with the setting on the top end. I am of the opinion nearly all your coolant fluctuations are related to an increase in GPU load. You can test this by running a CPU only stress test for 15 minutes. Doesn't really matter which one, but I am expecting a coolant delta of 6-8C with little to no increase in motherboard temp, 960 pro temp, and GPU temp.

So, if it is all GPU waste heat, what can you do? The above suggestion to turn the rear fan to intake does work in some instances. However, my specific testing on a 540 with two 140mm, 2000 rpm fans maxed out at the top on a 280mm radiator were horrendous. Within 20 minutes of gaming I destroyed my previous temperature records by more than 10C. Now, there is no danger in trying this and I think you still should, since every instance is different. However, I think the overall goal should be to move more hot air out the back and less out the top through the H100iv2.

There are a couple of things you can do to affect this:

1) When gaming, rear 140mm fan as high as you can stand. For me that is about 900 rpm (with headphones). A little less without. This is not an every rpm matters thing, but you want the waste heat going out the back and not through radiator.

2) Slow down the H100iv2 fans. If you are starting at 31C, you are going to get near that 40C=100% fan speed line all the time. There is nothing magical about this boundary. It is based on the amount of watts it takes to raise this volume of water by 15-20C. However, if you are starting of at 31C instead of 21C, you are going to hit the barrier every single time and those fans cannot reduce the heat below the case ambient. You are literally spinning your wheels. A few different ways to set the curve. One is to upshift everything by +10C (about the difference in the starting basis). Obviously this will be a non-issue in Winter. A more appealing way is to set the highest fan speed you can stand to one or two degrees above your highest normal coolant temp. So, if 45C is the worst, link that to 1600 rpm (or whatever), then set a nice loud spike to 2000-2200 at 50C. If you get out of your normal zone, you will hear it without having to look at Link.

3) The third recommendation is specific to the 540 and higher watt GPUs or SLI. Replace the 2x140s with 3x120. I like the AF140 and I miss the days when I could run 5 of them on the case. However, I ran an SLI set-up and the difference between any random 3x120 and 2-140's maxed out was at minimum 5C on the GPU and 4-7C on my older M.2 drive. Another issue with high speed 140's on the front is the blades will interact with those 120mm mounting flanges. I did not mind the AF140 fan on there, but other 140's did not fare so well. 3x120@1500 rpm will put more air through the case, with no real increase in noise. It will also be a more focused flow and in the short 540, you can reap some direct benefits on GPU backplate and m.2 drive surface temperature. A good 3x120 set of fans at 1500 rpm will move at least 150 cfm (ignoring your filter). That is far more air than you can ever remove through the top radiator and rear 140 fan combined. You will have your positive pressure. Normally, I down play this concept, however in this case you are trying to push more of the GPU waste heat through the back mesh and slats and I could always feel it coming out the back in this configuration. Those 3x120 will also do better against the dust filter than 2xAF140.