Jumping into Water Cooling a P180b Ver1.1 --Some Questions

[NeoMatriX724]

Hello!

I'm planning on watercooling my P180b and have a few questions.

Firstly: Here is the hardware I'm planning on cooling:

CPU: Intel Core 2 Duo E6600 Conroe w| the possible upgrade to Core2Quad
VGA: eVGA e-Geforce 8800 GTS 640mb Superclocked (Currently in the RMA process)
Case: Antec P180b Version 1.1 (has most of the P182b revisions rolled in)

I am an experienced system builder, but this will be my first foray into liquid cooling AKA...Total WC n00b.

As of now, I see a few possible configurations that I can do.


Setup 1)

Firstly, since I'm cooling a GPU and a CPU (especially an 8800), I think a single 120mm Radiator wouldn't do it, and at a minimum I would need a PA160. I would prefer not to dremel down the case that much and was thinking of running a 2-radiator setup, one on the rear 120mm exhaust and 1 on the front - middle 120mm intake. Each radiator would be a 120mm configuration. I was looking at a BIX or a MCRQP120.

The advantage I see with this is that I would probably only have to lose 1 drive bay. while staying 100% internal

How much of a performance hit would I see with that dual rad, and would that configuration be able to handle a 2 8800 GTS's in SLI. I am planning on using either a D5 or an MCP655 (depends on recommendations).

Setup 2)

On performance-pcs.com I saw a P180 which had a dual radiator (120x2) mounted to the top of the case using the top 2 5.25 bays. I figure I could rig a display of sorts into one of the top bays so as to not totally lose it. I would have to cut some fan holes, and radiator mount points into the top of my case (probably top it off with a Rad-grill or modder's mesh.

This would stay pretty internal, which I like, but also gives the radiator better access to air.

Is it a problem that the radiator would be on the top of the case and above the resevoir? (Would I have any bleeding problems?)

Setup 3)

I can mount a dual/triple rad on the outside of the case in back. I'm not too keen on this since it will then be quite visible on the outside, this is more for quiet, and performance than to show off. Though I would get better performance since the rad is outside. My case has the 2 rubber grommets in the lower right corner, just above the expansion slots. Does it matter if I mount my radiator with the barbs on the lower end?


As I get answers to these questions I'll upload some pictures of my box and some mockups of where I want to put things and what equipment I'm thinking to get.

Thanks!

 

[BillParrish]

OK will give it a shot, question 1 is mainly about rads and heat capacity so I will tackle it in a general way.

Rads have an unbelievable ability to dump heat (> 1KW) when they are given decent airflow. Even a single 120mm rad with a strong fan could easily handle the load. BUT everything is an engineering compromise, your loop temps would be higher than what most people would want, the fan would probally be louder than you want and your max OC if you where pushing the OC to the limit would probally suffer some. So I agree 2 x 120 should be the min rad configuration and it does not matter a lot if it is two 1x120 rads or a single 2x120 rad, your call, think about mounting options and tubing routing as you are, that will make the call for you.

Now if you read between the lines of the above, what it says is that the "usability" of a WC setup is dependent on the amount of radiator cooling surface and fan airflow, this is what dumps the heat. Another way to say it is that bigger or more rads allow lower airflow (quieter fans) to achieve the same level of cooling as less rads with stronger fans.
So that is the compromise you have to deal with, a 3 x 120 worth of rads would be better still no matter how mounted/configured.

think about mounting, routing in such a way an additional rad could be incorporated into the loop if you are not happy with initial results. (bottom of case is one option) .

No one can determine a "performance hit" if you used a single 120 mm rad and an 7000rpm delta fan on full blast there would be no performance hit, you would go deaf, but it would cool as well as a 3x120 with low/medium speed fans. Back to that nasty "everything is an engineering compromise," thingy

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#2

No, it defies intuitive reason but because the inlet and outlet of the reservoir are below the level of water in the res (or will bleed a little from the loop to make it so) the pressure of the air pushing down on top of the fluid in the res will prevent it from overflowing. Its actually pretty cool to have the res at the bottom of the loop and open the top and nothing happens, very weird when you first do it. But normal air pressure will support a column of water 32 ft high ! . No worries, just make sure the output of the res is connected directly to the input of the pump and in general its best to have the res at least slightly higher or at same level as the pump to eliminate any possibility of running the pump "dry" which could damage it.

#3
no, any decent pump will over a couple of days push all the air out, and of course you can just tilt or lay the computer on its side for a hour or two to help remove air. So just minor issues that can easily be overcome and (it seems to me) that the minor issue would be more than made up for by the ability to use the existing holes and keep things nice.

As a side note, I am a big fan (/groan) of providing the rad with cool ambient air no matter how you do it, feeding the rad warmed internal case air is a bad thing as the efficiency of the rad is hugely dependent on the delta in temp between the coolant flowing through the rad and the temp of the air passing over the fins (and amount of air too). I recommend med speed fans on a controller as opposed to low speed fans, you can turn a med speed fan down to "dial in" cooling vs noise but you cant turn a low speed fan up.

Have fun,

Predrill your motherboard mounting plate so you can access the heatsink/waterblock holes in the motherboard by taking off the right side panel.

 

[NeoMatriX724]

Thanks for the insights,

My idea for option 2 was to have the 2 fans on the rad be intakes pulling air from outside, and then leave the top-rear 120 on low as exhaust and and the rear 120 on med as exhaust as well, this way i'd be dumping the rad heat into the case but then it would be pushed out. there would still be a 120 circulating air within the case but that would be low, I'll draw a mock up of this in a day or so.

 

[xLiquidx]

What I did was mount it in the front top part of the case cutting a hole big enough for the Rad Grill from AC Ryan.