First WC PC - planning stage only

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I'm currently thinking through building my first watercooled PC to replace my current air cooled one, so if anyone could take a look at this and let me know what they think it would be appreciated.
I probably won't build this for 6 months or so (after I graduate and get a job!).

The main reason for watercooling is that I think getting really silent air cooling is going to be more and more difficult in future. As a result, I'm not really thinking in performance terms, but in accoustic terms in designing this system.

The basis of the plan is to watercool the CPU, Graphics card and Chipset. The radiator will be at the front of the case (behind a very un-restrictive front inlet), and a duct behind the radiator will suck air through it to a 120mm fan mounted on the floor, blowing air out of the bottom of the case. This is both for looks reasons (keep the back of the PC clear, not cut up the sides while evacuating hot air from the case), and so that any noise from the fan is at least slightly muffled by the carpet.
The main reason to dump the warmed air out of the case is that I intend to use one of the ultra-quiet thermally controlled power supplies, which often ramp up if the case temperature rises.
I would be reckoning on getting a 30cfm air flow from a quiet fan through the radiator - giving something like a 10 deg C rise in air temperature at full load, 1 deg C at idle.

I'm currently thinking of using an AquaTube reservoir mounted in the top surface of the case - I just think it looks superb, and would fit well with my plan to have an aluminium case.
Current thinking on the pump is to use an Eheim 1048 - from what I have read so far, this seems to be the largest pump that could truly be called silent. The idea is to run it off a relay so that it is totally silent (off!) when the computer is off, but I can't forget to turn it on.

The waterblocks is the area I am most unsure in, although I suspect for a system like this it may not be critically important. My current thinking for the CPU is to use a DangerDen RBX, with the GPU and Chipset each being cooled by one of the outlets.

I'm guessing that the best arrangement for flow/cooling is:
Pump -> Radiator -> CPU -> GPU/Chipset -> Reservoir -> Pump

I've got quite a few questions though:
1) What would be the typical effect on the amount of air pushed by a fan of putting a radiator in front of it?
2) Are there any brands of fan that seem to be partcularly quiet when coupled to a radiator? Conversely, are there any that are good normally, but make a racket when attached to a radiator.
3) Is the 1048 the best pump for the job, or are there others that are noticeably quieter?
4) Is it worth fitting a special valve in the base of the system when the time comes to drain it and change the coolant, or is this not a problem?
5) Are there any major problems with running the GPU/Chipset in paralell?
6) How much difference is there between waterblocks for this sort of application?
7) Is the water flow sequence the right way around? I've seen a lot of photos of systems where the pump seems to pump straight to the reservoir, but surely this wastes most of the pump head?

I'm trying to figure out all potential problems out in advance - it's far more fun than doing "flow induced sound and vibration" problems

Thanks - Paul F

[killernoodle]

You will need to put a filter on the intake fan due to the fact that it will be on carpet and will suck up dust.

As for the resevior, it would be much easier to build one with some PVC pipes. If you go for the manufactured resevior you will need to be sure it is mounted vertically on the case somewhere. You dont want to be sucking in any air (cavitation is BAD for pumps). Mounting it at the top of the case is good though, as the pump needs to be flooded for starting.

For the waterblock, really any one will do. The RBX will do fine, as will the swiftech 5000 series, the dtek whitewater, the TC-4, the spiral, the maze 3... ect. Whatever suits your pricerange. As you are cooling for silence, the waterblock decision isnt as important as radiator, fan, and pump. So, lets get this answering started:

1. The amount of airflow is reduced significantly, but it doesnt stop of course. Any amount of air flowing through the radiator will cool it, so having 30 cubic feet a minute is more than enough for decent cooling.
2. Get a fan with dual ball bearing. Panaflos by panasonic work great, so do the aluminum enermax fans. A rheostat of some kind to slow the fan down is also great for reducing noise.
3. That pump will be quiet, but I have experience with danner mags and they work absolutely beautifully. The mag 3 will out-perform that pump in every category, yet it will still be basically silent in operation. I cannot tell it is running by listening to it, I have to put my hand on the case and feel it running.
4. The resevior will likely have some kind of fill point as it is the most convienent to fill from. Typically, if the resevior is on top that is the best thing to fill from anyways. Also, you want the pump to be flooded before you get the liquid moving through the system or you could cause damage to the pump and create lots of annoying and performance degrading bubbles.
5.Not really, especially it they are restrictive. Typically, the CPU is the main object in the cooling loop and requires the most powerful cooling block and water combination. Adding restrictive blocks on the NB and GPU will rob this power if hooked up in series, but in parallel the flow will be much greater in the CPU area. This, of course, comes at a price. The GPU and NB will now only recieve half of the water used to cool the CPU, but the two do not produce much heat and therefore are not impaced as much.
6. Parallel waterblocks can be far more flow restrictive and still retain decent performance characteristics. You do, however, want to have similar designs utilized in both the GPU and NB as equal flow through both blocks is preferable. DTek and Polarflow use the same base for both their GPU and NB blocks and would therefore be ideal for this situation. Swiftech also manufacturers NB and GPU blocks with similar flow characteristics.
7. Your setup is great. You always want the resevior last in the sequence. My resevior connects directly to the pump inlet in a 1/2" NPT fitting (the largest size accomidatable (is that a word? ) for my particular pump-- it is much larger than 1/2" ID tubes) You typically want to avoid restricting the inlet of the pump and want either the radiator or the waterblocks first after the outlet of the pump. Other than that, route the tubing in the most convienent fashion or in a way that reduces the amount of 90 degree bends in your system.

I hope I have answered all the questions you asked.

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OK, thanks for that.
The intention is that the fan will be blowing air onto the carpet, with cool air coming in through the (ideally filtered) front air vent. I'll still have the normal dust problems, but they should be tolerable.
There's a photo of the res I'm thinking of using here. The idea is to mount it vertically into the top of the case, with the lid being removeable for filling. I was more thinking of if this would be a problem to drain the system to change coolant - the thought of holding a PC upside down over a sink doesn't appeal!

[killernoodle]

That resevior may require much larger fittings than it has. I doubt those are 1/2" ID, which is basically what you are using for the rest of the setup. As for the draining, you could use a T-Line going through the lowest point of the loop, then with a valve coming off the t-line so it could be opened and closed when draining.

Have you seen my resevior? It works really well, is connected directly to the pump, and is easy to fill.

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Apparently that res comes with various optional fittings, including barbs for 1/2" ID tubing. However, it seems to neck down to 1/4" at the entrance to the reservoir (just to be awkward). Depending on where I'm working next year it may be possible to drill out a couple of the holes at work and replace them with true 1/2" barbs glued in.

I have seen quite a few reservior designs that connect straight to the pump, and they are probably my second choice if the one I'm thinking of at the moment doesn't work out.