Tubes behind motherboard tray of Corsair Obsidian

Hi,
I'm new to the water cooling world but I have built many "air cooled" computers in the past. I've been planning for a while how I would install and route the tubes in my Corsair Obsidian case however I'm not quite sure yet... From the pictures I've seen from various water cooling builds, the tubes are always visible. For cosmetic purpose, I would prefer to pass the tubes in the grommeted holes and make them go through the back of the motherboard tray, in the "vent exit area" of the case.

I've measured the clearance in this space and it looks like it's about 25mm wide, so 1/2 hoses should in theory fit in there. I was thinking that using 90 degree or 2 45 degree fittings (like these http://www.watercoolinguk.co.uk/catalog/product_info.php?cPath=39_53&products_id=2066) would be pretty safe. But since I've never seen someone actually do that, I'm wondering if it is a bad idea. Would it affect the flow rate that much ? Is is too risky for some reasons ? What do you think ?

Thank you !

Welcome!

use 3/8" ID tubing if you want to do that, you still get good flow with it. otherwise check out 7/16" ID tubing for the best of both worlds (3/8 and 1/2)

what are the specs of the loop you want to build?

if it's a good pump you will be fine with a few 90's or 45's.

Thank you very much for the quick reply !

I'll try to give as much information as I can since you might have other suggestions for my overall build. So here are the computer parts I have:

Cpu: i7 920 D0
Motherboard: EVGA Classified
Memory: 3x2GB Dominator GT 1600
Hard Drives (Backup): 2x1.5TB Caviar Green In RAID1
Hard Drives (Win7 + Games): 2x120GB Vertex Turbo in RAID0
PSU: Corsair 1000W
Graphic Card: Radeon 5970 (BO obviously i'm still waiting to get it)
PhysX: Geforce 8800GTX

CPU Waterblock: Apogee XT

The other water cooling stuff i'm waiting to buy it because I want to make sure I've planned everything perfectly (so that's mainly why I need your help).

I have come to the conclusion that 2 loops would be best since I will be water cooling everything.

Loop 1: Res + Pump + CPU + Mobo (full waterblock) + RAD 120.3
Loop 2: RAD 120.2 + 8800GTX + 5970 + Res + Pump

I'll be putting a 120.3 Rad at the top of the case. I don't know if there is enough space to sandwich it, or maybe if I put 3x push fans then RAD then outside the case 3x fans in pull.

For the second loop, I'll mod the bottom of the case by removing the drive bay and put the 120.2 there, I've seen a post where someone else did it and it seems to have worked prety well. But since the RAD will be at the bottom, I would like to get the tubes to go through the holes that goes in the side of the case, then make em go behind the motherboard tray then go in from the other holes in the back so they would come out right next to the video cards. Then from the outtake of the GFX card, it would be routed about the same way to the Res, then Pump etc... Does it make sense ?

For the pumps, I was thinking 2 MCP350s.

Also, what would you suggest for the RADs and fans ?

The fans need to be black and very quiet, I'm shooting for a system that would be below 35 decibels loud. I want the best performance / look / quietness.

Thanks again !

I built a similar setup to you about 1 month ago
I think you'll be very happy with it

I used the eK multi-res's, primochill tubing 7/16th, compression fittings, Feser 480 rad, XSPC 360 rad, and DDC 3.2 pumps

keeps everything nice and cool!

good luck with your build..one thing I would suggest is to attach the fans on the GPU rad to a switch so you can turn them off at night/when not using the monitor.

you will not need the fans running on the GPU rad when not using the PC overnight and you will have a near silent system. (if you plan on having the PC in the same room as your bed) I use (4) Scythe fans on the GPU rad and while not loud, they are audible (I believe they are 1800rpm)

pumps are good and so you can do the 90's and 45's.

for fans i love yate loons, cheap and good fans, by far the best for the money.

Triple 120mm
ThermoChill PA 120.3- good for low speed fans
XSPC RX360- good for low speed fans
HW Labs Black Ice GTX360- good for high speed fans
Swiftech MCR320-QP- good for medium speed fans
Feser X-Changer Triple 120 mm- good for low speed fans
Black Ice SR1 360- good for low speed fans

Double 120mm
Thermochill PA 120.2 - good for low speed fans
XSPC RX240- good for low speed fans
HW Labs Black Ice GTX240- good for high speed fans
Swiftech MCR220-QP- good for medium speed fans
Feser X-Changer Triple 120 mm- good for low speed fans
Black Ice SR1 240- good for low speed fans

Thanks Spawn for the suggestions. I wasn't sure if I would go with ThermoChill or Feser. From what I've read, the Fesers are slightly better. Would you recommend them if price is not an issue ?

I'm a little confused with the tubing size, it seems every parts of the loop are using different tubes dimensions. My Apogee XT uses 1/2, the ThermoChill 3/8, Feser 1/4... My understanding is that the bigger the tube, better is the water flow, but smaller tubes are easier to route and are less prone to kink. Are there any downside from using adapters to make all those pieces fit together ? Could I use 2 Fesers, the 120.2 with 3/8 tubing and the 120.3 with 1/2 tubing ? Would it be the best choice ?

Thanks Techlogoblin for your switch idea. This is exactly what I need ! Actually the computer is in my bedroom, so I guess it would be nice to hook a fan controller on the 120.2 and turn it all the way down when I go to sleep since I won't be using the GFX card. That would allow me to use the Scythe fans at max speed while gaming for max performance (I'm using Headphones anyway so if they're under 40 DB it should be alright).

You are confusing the threads on the barbs with the size of barbs themselves. Most everything but the Thermochill uses standard G 1/4 thread size. The Thermochill uses 3/8 BSPP threads. You can get any of the threads in barb sizes 3/8 or 1/2.

Fitting threads for everything except the Thermochill rads is G1/4 threads. Thermochill uses G3/8. You can buy barbs with G3/8 threads. You can buy G3/8 to G1/4 adaptors if your going to use compression fitings.

Tubing is always measured in OD AND ID. Since you'll have both loops without lots of parts (restriction) you'd be fine with 3/8" ID hose. Barbs and compression fittings OD equals the ID of the hose. Compression fittings you have to get exactly the ID/OD of the hose your going to use.

Looks like your going to mount the rads horizontally. So Yate Loons are out. They have sleeve bearings, you need real bearings. The Yates will fail early, in a year or so.

The difference between TC and Feser is not worth metioning, or the Black Ice SR1 series, or the new EK rads. They are ALL low FPI good rads.

Nice idea, post pics when your done, id like to see a wc setup with most of the tubes hidden

Thank you for the explanations, I am now ready to order the water cooling stuff.

markp1989: I already have a Web Site for that project. I'll put unboxing and assembly videos on it. I'll post the link in 2/3 weeks.

I think you're going to have trouble with 90 degree bends in such a small space, you could go for black tubing and it will look stealth.

I'll go for black tubing anyway but why do you think I will have trouble with that ? Do you have an Obsidian case ? Have you seen someone try that ? It seems there is enough space there to make the tubes pass in and out. I might have to mod some minor things on the back to make sure it is not squashed against the back panel but overall I haven't seen any major problems. Did I miss something ?

you can use 2 long sweep elbows from the block to the edge of the motherboard, then you will need a sharp elbow to go behind the board/tray.

Yea I was thinking a combination of long sweep / sharp elbows would work. My primary concern was that I wasn't sure 90 degree or 2 45 degree elbows were a good thing (since I haven't seen a lot of systems using them). But if Spawn is right, if I can manage to place them correctly it would still work (It might not be the optimum setup since that would slow down the water flow a little but considering I have a decent pump it should not cause any troubles).

Look at the bitspower 90/45 deg fittings. They are very low restriction, a very nice sweeping curve. And can swivel. Mucho popular.

ya your pump will be fine, i would say most people only use 40% or so worth of there pumps potential.


another idea would be to build a sheet metal top right above the motherboard and have the cpu block tubes go into it. using 2 of these fittings.


or even look into a few of their fairly new snake fittings.
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&products_id=25818

I really think the OP need to get the case and look it over before ordering the fittings, yea there's enough room to hide wires and cables but to hide the WC tubing he's going to need to keep the R angle fitting fairly tight to back of the motherboard tray.

I already have the case, so here is a pic of what I want to do at the back (sorry for the bad quality of the picture I quickly used my IPhone instead of a proper camera).

Yea, even running bitspower 90's and 3/8 ID tubing he might need to bend a bit to make the fitting ID work. Only know after he tries.

OP: Just do it.