Peltier instead of radiator in WC setup?

[R.C.Anderson]

I've just been browsing some watercooling equipment, and an idea came to me, what would it be like to get rid of the rediator out of the watercooling setup, and instead get a peliter cooler, and attach the cold side to a heatsink submerged in the reservoir, and cool the hot side with either a large passive heatsink, or a decent CPU HSF?

I've had a quick googling session on the matter, but have only found people who have tried it with old components (back in the P3-P4 days) is this because they just couldn't handle the higher heat output of the newer chips, or have people just not been interested?

I would love to know, as if I get a watercooling setup, a reasonable peltier is a similar sort of price to a decent radiator from what I remember.

 

[R.C.Anderson]

You place the peltier on the chip and the cold side cools the chip. Then you have to use watercooling to cool the hot side. So you still have a normal watercooling loop but it is cooling the peltier instead. For a peltier you need a seperate power supply. There's a bit of information about it in the cooling sticky.

Yea, I've seen that, however my thinking was, if it was a decent enough it would be able to chill the whole cooling loop, so the gfx card, and NB is also cooled by it, rather than having to buy multiple peltiers.

Another think I thought of was to use a peltier as well as a radiator, in an order similar to this: waterblocks>radiator>reservoir with peltier>pump>waterblocks, as this would allow the radiator to take out most of the heat (as it would in a normal setup) but then the water would be able to be cooled to slightly below ambient temperatures (I would do some calculations, and get a micro-controller to control the peltier to keep the water above the dew point (Electronics is my thing, so making the micro-controller circuit, and programming it would be enjoyable, and doable)) This would also allow a lower powered peltier to be able to be used. Any opinions on this?

I've also just checked prices on peltier cooler, and I can get my hands on a 200W for around £25 (from farnell, so avoiding ebay) and the PSU isn't a problem, as if I get a new build, I'll be buying a new PSU for it, so I'll be able to use my 450W corsair that I have in my current machine.

 

[R.C.Anderson]

The wattage a radiator removes is linearly proportional to the temperature difference between water and air. C/W values are available online. If you try to bring the water below ambient, the radiator will now be working to warm up the water. As such, a radiator in the chilled loop is brilliant as a means of preventing the water going too far below ambient but a really bad idea if you want it to go sub ambient.

the idea I had was that the water going into the waterblocks would be sub-ambient, however the water coming out of won't be for example:

Reservoir with peltier (10C)>Pump>Waterblocks (30C)>Radiator (25C)>Reservoir

That's just an example (no idea what any of the temperatures would actually be) with the temperatures being the coolant temperature as it leaves that comonent.

The general advice is not to use atx power supplies with peltiers, for fear of killing the psu. If nothing else, be aware that your 200W pelt is probably rated at 200W, 15.4V. If you run it at 12V, you need to downrate the 200W considerably.

I've actually just noticed that it's rated at 24V, so I would either buy/make a seperate 24V PSU, or I would switch the 12V output of a PC PSU upto 24V, but the electrical side isn't what bothers me at the moment, it's whether there would be a sufficient performance increase from this?