HELP, not sure how to route a high end water loop for ideal temps!

[faxon]

So I've got a conundrum of sorts. I have a loop consisting of two 290x and a 4790k with 2 Alphacool Monstas (3 fan 120x80) and a swiftech MCR320. using EK copper blocks on the 290x and the new Apogee XL with a custom biohazard plate from performancePCs, and the best temps my CPU will do are whatever my GPU load temps are. The cpu is down loop from both GPUs and is getting cooled by water which has just past through both cards, so i'm limited in how cool i can get the CPU because of this. I know that normally in a water cooling loop, the water reaches a steady temperature after operating at load for an extended period, but when it's a hot day out this means that my CPU is idling at 60c.

I havent gone to overclock it yet because I need to make some other modifications to the loop anyway, and I was wondering if anyone had ideas for what would be best to keep this beast of a loop cool? I have an extra black ice extreme GT2 I could put in the loop after the GPUs but before the CPU possibly since I havent put a radiator in the top of my case yet, everything else is compartmentalized into HAF Stacker 915 units. I have a D5 pump with dual outputs so adding another radiator and running the CPU + that radiator would be easy without adding my second D5 to the loop as well, but there's plenty of space in my case and I have another reservoir as well so it wouldn't be an issue, but my knowledge of watercooling tells me the only way to get that CPUs idle/load temp decoupled from how hot my GPUs are running is to run separate loops. Anyone more pro than me want to chime in?

Photos bellow for those trying to imagine how it's all set up. I was hoping not to put a radiator in the top so i could put an all air cooled unit on top and have it safe from any leaks that may happen in the future, but now that I've figured out which of my two old radiators was the one leaking (pictured running with the red fans, why I'm rebuilding, the MCR320 is going in its place), I'm more concerned with the top system's total performance and can stack that ITX backup in underneath the beast. Also, currently one of the Monsta radiators is venting inside the (middle) case, i'm switching the entire radiator stack to full exhaust so i'm not venting hot air into another radiator or inside the case since my PSU's also sucking up heat and running at near the radiator's exhaust temps. Im also using a 10% glycerin coolant i mixed myself this round because in the past i used a pink PG based dye and it gunked up two of my other radiators, and it's worked nicely to dissolve all the left over crap along with the hot water, so I need to empty it ASAP to rinse everything and reloop it again with emerald green tubing to match the secondary reservoir.

http://imgur.com/F47tkbx

 

[aigomorla]

do you have temp probes anywhere in your water loop?
i would need you to do a coolant test to see what your temps are via coolant.

What fans do you have on your rads also?

 

[faxon]

except for on the MCR320 i'm using silverstone air penetrators, im using medium speed yates on the swiftech radiator cause it's always worked well with those and they're the best looking green LED fans around that work well. I don't have a temp probe but whatever load temp my GPUs hit (right now 58c) is usually within 2c of my CPU idle temp. The CPU is consistently idling at about 2-3c under whatever my GPU load temps are, and if I were to open OCCT and fire it up the CPU instantly hits 85c and shuts the test off unless i run it in 32bit mode. I also have access to a stack of swiftech's AP15 knockoffs that i can use to test vs the air penetrators, my buddy kept them when he sold me the second radiator to use later when he rebuilds his loop with parts that fit in his case. If water temp can be measured from anywhere in the loop, I could always stick a probe in through the fill port on my reservoir as well, if I can find my multimeter and probe

 

[aigomorla]

yeah i would need a water temp....

If the water temp is high, it means either you have too much heat load, or your not getting enough air though your rads.

If the water temp is low, it means either block contact is not that great, or your lacking the required flow.

 

[faxon]

water temp is definitely on the higher end, i can attest to this by using an IR thermometer to check the temps externally and i'm getting temps ranging 95-105f on the tubing and as high as 115 on the fittings. The direct backside of my hottest 290x is 105f to give you an idea of how well the blocks are pulling heat away from the GPUs, even when heat travels upward.

I'll dig around this week and see if i can't find my probe (i think fry's may sell replacement thermal couple probes for my unit since it's a fluke), found the DMM in the bottom of my spare system parts/cables box! My main concern right now is that the radiators aren't getting enough cool air because i can literally feel the heat radiating out of them at load from 5+ feet away due to the static pressure from those air penetrators, and the fact that corsair link says my PSU is running at like 48c as well and feels quite warm. switching the entire case to 100% exhaust will hopefully get that running cooler as well. there's a nice big wide opening right in back of that case where a PSU can go so the static pressure from an all exhaust setup should easily be able to pull in fresh air through there.

I'm fixing the leaking radiator and switching the fan placement tomorrow, the leak needs to get fixed regardless and the fan swap is quick and easy to deal with with almost guaranteed improvement due to more airflow through the rads. If it's still an issue then i'll probe the loop temp and see whats going on. I'll dismount the CPU block and inspect the TIM displacement as well, it's had plenty of time to cure in and it was fastened down as tight as the swiftech mounts they give you allow for. If i used to much i'll cut a plastic bag with a razor blade and use it as a stencil to spread the TIM thin with said razor before remounting, like i did back when i had a lapped block + chip. I doubt at all that it's the block itself either because when i let both GPUs idle the entire loop idles in the 30s, and the cpu left to load while the GPUs are idle typically are lower than what my 2600k hit while overclocked to 4.6GHz at 1.365v. i'm thinking not enough airflow through the rads/not enough rads and so the loop is just retaining to much heat for to long, allowing the CPU to act as a heatsink rather than the loop removing heat from it until it springs to life to actually do work.

If it's still not doing well after this then I'll look at that top 2x120 slot for another radiator. I actually owe the working GT2 to Shmee as part of the trade that got me the second Monsta, so if it needs more i'll just get a 2x120 Monsta to go on top where those two air penetrators in the top are chilling already. you can see where the LED strip on the right of them is there's ports for water cooling barbs to come down and it's a clear shot to the right for my reservoir and a clear shot up from the CPU beforehand

ed: did i mention that once the temps outside drop low enough the entire loop drops 10c just from how much cooler the ambient air is? between the time i posted this and now the entire loop dropped 10c. You wanna play connect the dots with me aigo? it's been a long time but I've learned everything I know about watercooling from you and I'm glad to see you're still running the show, I'm just looking for validation of if my assessment of why it's not working to peak is correct or not, since it's been a few years since i was active here and the cobwebs are strong with this one. I'll post some build shots of me and shmee tomorrow during so you can see how everything is routed internally, it's incredibly simple and there's room to make it even easier to run as well since Alphacool is putting tri directional mounting options + back side fill/drain ports on all their radiators now. It took me 45 minutes just to fill it last time because i had to bleed so much air out just to get water to the pump, gonna put a fill port directly into the back port on the radiator that feeds the pump intake 🙂

 

[aigomorla]

yea im willing to help you out and fix your system.

Also monsta's were notorious for being restrictive in air flow.
You may need a stronger fan, like a 38mm fan, or you may need to sandwitch the rad with fans... push / pull.

I really dont see any other reason why your water temp is that high.
Not unless its a steaming 95F in your room all the time.

 

[guskline]

Want to borrow my Mo RA3-420?:biggrin:

 

[faxon]

yea im willing to help you out and fix your system.

Also monsta's were notorious for being restrictive in air flow.
You may need a stronger fan, like a 38mm fan, or you may need to sandwitch the rad with fans... push / pull.

I really dont see any other reason why your water temp is that high.
Not unless its a steaming 95F in your room all the time.

80-85 actually. thats part of why I'm using water at all, during the summer it just gets so damn hot i needed to spread out the space over which i was dissipating heat in order to run a nice 290X crossfire setup without it sitting there at 90c+ loads 24/7. at least the GPUs are hovering in the 50-60c range between hottest and coolest time of the day which is totally reasonable, I'd just like my CPU to also have this benefit, thats why I originally bought the MCR320 and my first D5! Anyway if switching the orientation of the fans doesnt help I'll look at my options for push/pull on the bottom Monstaa and 38mms for the top one since it has to have enough room to fit inside with my MCR320, that way I don't have to buy new fans. You're probably right that the radiators aren't getting enough airflow, I put a digital room thermometer inside my top radiator box where the monstaa with the most airflow is venting inside the case (and thusly why my PSU is running so hot) and it's hovering around 100 degrees, so one of my radiators is simply not getting any cool air right now at all. Will post back once I can get a car to go pick up shmee and another 2 gallons of distilled

 

[faxon]

Guskline i didn't see your reply before. I'd love to except i don't have a good spot to mount a 4x4 120 radiator nicely. I'm pretty sure it'd do the job though LOL. I redid the loop and with all exhaust fans I got a decent drop in temps but still my cpu is heating up to the temp of the cards. I'll look around and see what's available for thicker fans and if that isn't enough then I'll legitimately look at mounting one of those RA3-420's in the previously mentioned window next to my computer! Currently I'm getting a 3-4c improvement but it's night time so let's see if it holds up during the day at full load. coolermaster may also have a HAF Stacker door with a fan mount out that can take a 200mm square radiator on the side of the rig if I want to keep the whole loop inside the rig.

 

[guskline]

Faxon, I have it mounted on the pedestal feet and connected to the loop via Koolance QD4 Quick disconnects. It and a XSPC RX360 give me PLENTY of rad space. BTW, it is a lot bigger than 4x4 120. The MO RA3-420 uses 9 140 mm fans per side.

Here is a photo of it next to my CM HAF 932 Adv

 

[faxon]

lol holy fracking hell that's a big rad. given my whole having access to a window to put it in that would be pretty much THE way to get it done, and the window's opening is exactly 520mm which would be enough to sandwich 3 140mm fans to hold it in place with some bricks to hold it up on the sill. Also since it's rated for lower speed fans I can stack push/pull yate loons on it on the cheap and get awesome performance without having to spend a bunch more money if i don't want MY only issue is what do i pick out to mount fans onto it? it just comes with a bare radiator and no fan mounts/grills and i don't know where to start looking for what i would need. I'm buying off the shelf parts, i still live with my parents even though i own my own business now and they won't let me turn the garage into a proper workshop because there isn't room for some kind of CnC or drill press or anything

 

[faxon]

an after the weekend update, i added the working black ice GT2 in up top because i literally just had to cut the existing final drain tube and catch it in a bucket, then reconnect the split ends to the radiator in place. installed it with push air penetrators and the pull D12SM-12 yates i've always had installed on it and that small addition alone has my cpu running at a decent delta difference than my GPU temps now, and the entire loop's temps are running better as well from the switch to all exhaust. Given how much I've already spent on fans and how powerful this loop could be if set up right I'm willing to sink the dough for some solid ones. I'm trying to stick within a 30-32mm fan range because of space limits inside the case, there DOES need to be enough space for everything in the radbox that's also holding my MCR320 and I'm hoping to push/pull both monstaas. the fans i'm looking at now are Silverstone FM122 fans (i'm honestly wondering why i didn't get the 25mm FM121 initially, they're basically air penetrators for radiators). I've got a constraint on fan hookups at the moment as well and they specifically come with the molex pass through that i need to make adding a bunch more fans easy, and the monstaas came with screws for 25mm and 30mm~ fans out of the box so I don't have to spend a bunch of money on special screws and things. thoughts? My goal is to eventually get this loop running so well that I can add another 290X and run that 4790k up to 5GHz or something ridiculous all at the same time.http://www.silverstonetek.com/product_legacy.php?area=en&model=fm122

http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=36_1130_403&products_id=4633keywords=silverstone+fm122

the other option i was looking at was panaflow 3000RPM fans but they're a decent bit louder and I'd want to get a fan controller to run the entire set of 6 for when i do and don't need them running, and i'm worried that a 3000RPM fan's motor will produce to much low frequency audible hum which will bother me to no end even when they're not spun up like jets. They're also cheap as shit though so if you don't think there's significant motor hum with them then i'll see if i can find them in a 30mm or 32mm (or please recommend me something similar). Finally, when using unmatched fans in push/pull where is it generally better to put the more powerful fan? i put the penetrators in push with my GT2 and i can feel it's moving significantly more air out of the radiator than it did when it was just a yate loon sandwich. Also, if I'm using a louder fan as a push fan into a rad as thick as the monstaa how much of that noise level is from the fan itself vs the airflow? if it's mostly airflow noise and not fan buzz then I'm not complaining about 42DBa while I'm mining sleeping or gaming because i have a 20" box fan blowing air around my room at night when i sleep and a hepafilter running, it's just during the day when I want to maybe bedroom DJ or listen to music on my monitors when it becomes an issue. that's one of the things i always loved about water cooling is it's great for computers that have to go in rooms with audio gear 😀