What radiator is right for me?

Robanada

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Hey Tom's Hardware, I'm doing the submersion cooling project, that i'm sure most of you have already seen.
In short, I need to keep a 5 gal tank of mineral oil <30 oC. Ambient temperatures will be 20oC to 25oC, and I'm going to put a 430W heatsink in the tank.

Now, I've seen some radiators with wattage ratings on them, but that doesn't really make sense to me since it seems like the wattage would be determined by the difference in temperature of the liquid and the air, but that's not hte point here. The point is that I'm a total newb to liquid cooling (never done it before), and I'm lost on what radiator to get.

I really like the sound of the Black Ice GT Stealth series, since I'm partly doing this project to keep noise levels down (<20 dB fans, ~50 CFM each), but I could sacrifice silence to preserve my fish =)

Thanks for the help, guys!
Robanada
 

wuzy

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Most bang-per-buck with minimal flow restriction rad is currently the Swiftech MCR320.
If you have cash to blow you can spend it on Thermochill PA120.3, they are quite thick so make sure they fit your project (60mm + 25mm_fan). Their design suits low rpm fans which is what you're looking for.

The GT Stealth series with their dense fins actually require fans with high static pressure (>1600rpm or 120x38) to perform well so they do not fit your need.
 

Robanada

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Hmm...well, I have a 475mm x 350 mm place on which to mount this (these) radiator(s).

I've basically set out 250 bucks for a pump, radiator, and fans, so I could go for the thermochill PA 120.3, or the two (or three) Swiftech MCR320's.
What do you folks recon would be the most efficient?
The whole stacking thing doesn't make much sense to me, personally. It seems like if you're pushing warm air from the first radiator through to the second radiator, there's less of a temperature differential, and, according to Newton's law of cooling, the second radiator will be less efficient. So, it would seem that placing them side by side would be a more efficient option? (space is no issue here :) )

Also, could you guys take a look at fans for me real quick? I'm thinking of these:
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103061
But I'm not sure... is 90 CFM per fan enough?

Edit:
Oh! Also: I'm looking at pumps, and I was hoping to find a submersible one, so that I wouldn't have to worry about noise from it. Do you guys know what makes a pump submersible and what doesn't? If there aren't any submersible pumps, can you recommend one for pumping mineral oil? I'd assume I'd need high head, because of the viscosity of the oil, but I have no idea on flow rate? High flow rate means cooling a lot of liquid a little bit, whereas low flow rate means cooling a little liquid a lot, so...is it a wash?
 

c0der1020

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You are spot on with the stacking thing.

The MCR320 is without a doubt better bang for your buck. Tests have shown that the PA120.3 is a little more effective than MCR320 but it's really minimal (atleast in all the tests i've seen).
 

wuzy

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Two MCR320s in the space of 475x350mm should do nicely.

I find for a low pitch (less annoying than high pitch to human ears) setup with low rpm fans in push-pull setup is very effective.
For two 120x3 rads you'll need 12 fans for that and to get them cheap in bulk we commonly use Yate Loon D12SL-12.
 

Conumdrum

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There is NO quality pump used in todays watercooling that is submersible. The pumps are so very close to silent already that we use. They are so much quieter than the old style aquaruim pumps that go 'digga digga' long ago. If anything they make a low hum. I have two 355's with XSPC restops. If i listen closely when my PC boots, I can hear them spin up. The wind outside my window drowns out all of it.

The D5 aka MCR 655 or the MCP 355 are the only ones really used anymore. So stick to those, you won't be dissapointed.

If your budget is only $250, please, unless you live in the UK, look at the MCR Swiftech rads. If in the UK, get Thermochill rads. For the money and capability they CANNOT be beat. I could smother you with charts, spreadsheets, and tons of recommendations.

A pump for mineral oil? I won't comment, I know nothing about that except why the hell would you want to pump mineral oil?

The Yate Loon lows or mediums from Petras is also the best bang for the buck.
 

Robanada

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http://www.youtube.com/watch?v=PtufuXLvOok
=)


Last question guys: before I get the MCR320's, their site says that they're optimized for low-medium output fans. I thought I read somewhere that the approximate cutoff (where they started being noticeably less effective than some other.. GTX..thing?) was at 130 CFM. Does this mean that I should be shooting for 65 CFM (in order to minimize noise), since these fans are going to be in a push/pull config?
 

wuzy

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130CFM for a 120mm fan is howling! I have Delta 120x38mm that does close to that which I use for sub-zero benchmarking. They're designed for use in servers.

Most ~1600rpm(considered medium output) which best suits the MCR320 are around 70CFM. Two D12SL-12 (low output) in push-pull setup as I suggested above will be better. In terms of hearable dBa they may not be quieter than one D12SM-12, but the sound pitch is of much lower freq.

e.g. I use six D12BH-12 in push-pull on my rad which @full speed churns out 2300rpm 89CFM, totally unbearable. I tune them down with a single PWM fan controller to around 1200rpm for normal use, and higher when doing 24/7 rendering.