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Advice for high restriction loop (change loop order or add another pump?)

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rtlflat

New Member
Joined
Aug 24, 2014
First custom loop build here :attn:

temps are fine, even prime95 for hours at 5.1ghz (non-avx) ~72-74C
during gaming cpu rarely hit 50s and gpu stay 40s (both overclocked)
But at 100% pump speed I'm only getting ~.6 gpm flow. This is after upgrading to 1/2" id tubing (3/8" id was only .3 gpm. but also reduced number of fittings which im sure contributed to this as well tho)
I didnt pay to have a nerfed loop tho, so I'd like to try and figure out best option to get up to at least 1gpm and unlock the remaining cooling potential

Components
Case: Fractal Design R6 TG w/ USB C upgrade
Motherboard: Asus Formula Maximus XI (with integrated VRM block)
CPU: i7-9700k (delidded/binned at 5.1ghz by Silicon Lottery)
CPU block: EKWB Velocity
GPU: EVGA RTX 2080 (2115ghz overclock)
GPU block: EKWB Vector block and back plate
Reservoir and pump: EKWB D5 140 PWM combo w/ x3 multiport top added

Radiators: Koolance HX-CU1020V 360mm x2 <<<<--------[main restriction culprits here. see review/restriction test here--->] https://www.xtremerigs.net/2015/07/30/koolance-hx-cu1020v-360mm-radiator-review/3/

tubing: Primochill 1/2" ID clear flex
Fittings:
Barbed: 1/2" ID EK fittings
Bends: Koolance Swiveling Elbow Fitting (Low Profile) x3
EKWB Swiveling 90 x3
EKWB Swiveling 45 x1
EKWB Swiveling dual 45 x1
Tees: Barrow G1/4" Thread 3-Way Block Splitter x1 (for temp sensor)
Flow meter: aquacomputer high flow USB x1
Other: couple swiveling straights and M-M or F-F straight adapters as needed.

1 1.jpg
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So basically I'm just trying to figure out if I should try and optimize current loop or just get another D5 to put between the current pump res combo and rest of loop.

Ideas for optimizing current loop:
1. make a custom bracket for vertical radiator on front, allowing me to point fittings into the case in the basement, instead of out of case on top. this would eliminate (at best) 2x low profile 90s, 1x swivel 90, and 1x 45-45 swivel fitting OR depending on min tube bend radius possibly will need to use 2x 45-45 swivels to point up out of basement.

2. reroute tubing to eliminate the long loop between motherboard block and cpu block (inlet). min bend radius so large that loop interferes with glass window so i have to push in and use thumb screw to close. window doesn't normally require thumb screws to hold panels on.
also the discharge of pump is 180 to first radiator. could send straight to cpu inlet, although I'd have to move others down the line around too to allow this configuration

Leaning toward getting a second pump and cramming in basement, although id probably reroute tubing a bit at same time. Rather not reroute, test, get another pump, test.... whatever I do id like to do just once more and be done. Tired of drain/fill/bleed so many times when my temps really arent issue. interfering with my COD time.
 

maxfly

Member
Joined
May 7, 2005
its really hard to see where everything is connected from those pics(to small for my old eyes). from what i can see there are some ways to shorten up your runs. i usually run my tubing, from res/pump to 1st rad- to cpu block- to 2nd rad- to gpu block- back to res/pump. running the loop like that usually ends up with the least amount of tubing. either way if your temps are good i wouldnt worry about it. like SS says another pump isnt going to help your temps any, maybe a couple of degrees. the only real reason to add another pump would be for redundancy. which is how i have my loop set up. but hey its your loop! do it up and let us know what you find ;)
 

MrLowe

New Member
Joined
Dec 12, 2018
Location
Eastern NC
I am running a pair of D5's in current loop for 1.8GPM, with both on "5". Using just one I get 1.1GPM. This is with 3, 140x3 rads and a 120x3 rad, a GPU and CPU block on 3/8" tubing. Two rads are Aquacomputer Airplex and one is a Waterchill? HTSF4. The other a Swiftech MCP series i think. The Airplex and HTSF4 are not the best when it comes to flow rates from what i have seen. With about four times the flow you had when running 3/8" the Koolance rads you have must be pretty harsh.

I currently have only a couple 90 degree fittings, so maybe that is one of the bigger things hurting your flow, as others have mentioned. As well as possibly the VRM block on the motherboard.

I do see about a 60% increase in flow from the second D5 pump, so adding one should bump you up about the same, so that might put you at or just above 1GPM, especially if you can cut out or reduce a few of the 90 degree bends.

That extra flow probably won't do tons for temps, but I like to be somewhere between 1 and 2 GPM on flow, and having the redundancy of two pumps is a good bonus too.
 

Flat-6

Member
Joined
Jan 30, 2015
Location
Australia
Ideas for optimizing current loop:
1. this would eliminate (at best) 2x low profile 90s, 1x swivel 90, and 1x 45-45 swivel fitting OR depending on min tube bend radius possibly will need to use 2x 45-45 swivels to point up out of basement.

2. reroute tubing to eliminate the long loop between motherboard block and cpu block (inlet). min bend radius so large that loop interferes with glass window so i have to push in and use thumb screw to close. window doesn't normally require thumb screws to hold panels on.
also the discharge of pump is 180 to first radiator. could send straight to cpu inlet, although I'd have to move others down the line around too to allow this configuration



Eliminating or replacing a handful of fittings is going to do nothing for your flow - you will be simply wasting your time as 90 degree fittings have minimal impact on flow. Check out my DejaVu build as it has tons of 90 degree fittings - more than double/triple of most builds.

The biggest culprit are the rads - until you replace these you will be stuck with a relatively large restriction which will be in your loop no matter what other things you change.

Imagine that the rads are simply a 'blockage' in the system - no matter what you do to the other parts of the system, the blockage remains.


Leaning toward getting a second pump

Don't waste your money - put it towards lower restriction rads.
 
OP
R

rtlflat

New Member
Joined
Aug 24, 2014
thanks for input guys. Found notification email in spam folder so just now reading these. I may just deal with the low flow as my temps I am completely fine with. Radiators do a awesome job keeping temps down... they just keep the flow down as well so i don't think they are reaching their max potential. considering some other tweaks though that may end up being more cosmetic than performance enhancing... we'll see

I think fabbing a sheet metal adapter so i can mount ports on front rad facing in at the bottom instead of facing away at the top will be my first task. fan/rad mounts there are slotted but 120mm slots don't extend up far enough to get enough clearance at bottom for ports. will eliminate 2 low profile 90s and a swivel 90 and swivel 45-45 that way. even if those fittings aren't significantly impacting flow it will at least look neater.

and since I have to take almost 3 weeks off work for holidays :mad: (workaholic) so I'm planning on designing a distribution plate/reservoir combo in cad (im a piping detailer/cad monkey for a living) and milling on my cnc. Idk if i can improve flow this way but at least it should look badass once i get put together.
 
OP
R

rtlflat

New Member
Joined
Aug 24, 2014
Have you seen Radikult's videos on Youtube? Should be pretty helpful.

thats actually where i got inspiration for this project. I've seen the sponsored custom rigs with distro plates before and I've had a shapeoko 3 cnc for a few years and just never connected the dots to realize the possibilities until stumbling across his youtube videos the other day.

and slightly off topic but I hope somebody here will appreciate this. I showed my g/f and got a look like i had come up all proud "cuz i make poopy"

tapatalk_1511286309947.jpeg

its a carbonator from a coca-cola fountain drink repurposed a water cooler for a tig welding torch (not my idea or design. credit to some genuis on weldingweb forum) :clap: works great for cooling torch but in most cases is not a chick magnet

too loud/big to fit in computer case tho