Anyone gone down the quite large reservoir road?

cavemanoc · 26 Nov 2011 at 10:38

you would be better off with one of the old school pond pumps (I think I used to have an eheim(sp)) - they give a much better head pressure - the down side is they add more heat to the loop - not really an issue in your case with the huge rad

BurntOutMutha · 26 Nov 2011 at 11:29

weird_dave said:
Submerging the rad in water will be worse if you're reducing the surface area of your water volume in contact with air (assuming final equilibrium is allowed). You'd be better off just adding another rad.

edit:

What rad? If it's a standard household one, that rating is the output at a delta of 60 degrees.

A delta of 20 gives you about 100W dissipation

Thanks Dave, I assumed that the heat would transfer more quickly is the rad was plunged in water than air...my mistake. But if that water than the rad sits in freezes that's gotta have a negative impact on temps no ?

This is the rad - http://www.diy.com/diy/jsp/bq/nav.j...506&fh_location=//catalog01/en_GB/categories<{9372014}/categories%3C{9942012}/categories%3C{9942038}/specificationsProductType=steel_panel_radiators/specificationsSpecificProductType=single_steel_panel_radiators

To be honest, i'm no expert on the theory (clearly) all I can tell you is with this setup I've dropped 10oC off my idle temps and never go above 60o @ 5GHZ. The temps rise only about 3c after about 2 hours use. The cpu is the only block being cooled at the moment (my 6950 is in the repair shop) so I expect temps to go up again, but then again I expect the exterior temps to go down so fingers crossed.

Edit - MCP Pump btw and I'm getting great flow with about 5M of tubing.

sunama · 26 Nov 2011 at 12:16

Eheim pumps are built to last.

I've had my Eheim 1048, for 10 years and it hasn't let me down yet. I have a spare Eheim 1048, which I bought, just in case my current pump broke (I don't want any computer down-time) and I have not yet had to use the spare.

I wouldn't use any other brand, other than Eheim.

Zack101 · 26 Nov 2011 at 19:58

BurntOutMutha said:
Well this thread has inspired me to move to an outdoor passive rad. Picked up in B&Q for £20 (400w rated), no more fans, the rad is outside (via 2 holes drilled for the tubes)....it's superquiet and my temps are wonderful .... bring on the winter, next I'll be submerging the rad in water.

Was thinking of doing this myself, do you think there will be condensation problems in the winter though?

BurntOutMutha · 26 Nov 2011 at 20:11

Yes i suspect so, one of my cores has already min temp'd at 1oC so i'm expecting trouble

weird_dave · 27 Nov 2011 at 13:57

BurntOutMutha said:
Thanks Dave, I assumed that the heat would transfer more quickly is the rad was plunged in water than air...my mistake.

well, you are correct, the problem is over time, the water the rad sits in will be warm too, it's the cooling of that water which is then issue. If you don't run at full load all week you should be ok, as long as the water container is big enough to soak up all the heat. To save space, a 2nd rad would be better and cooler, and probably cheaper.

BurntOutMutha said:
But if that water than the rad sits in freezes that's gotta have a negative impact on temps no ?

If that water freezes you might run into problems if you switch the PC off overnight.

BurntOutMutha said:
To be honest, i'm no expert on the theory (clearly) all I can tell you is with this setup I've dropped 10oC off my idle temps and never go above 60o @ 5GHZ. The temps rise only about 3c after about 2 hours use. The cpu is the only block being cooled at the moment (my 6950 is in the repair shop) so I expect temps to go up again, but then again I expect the exterior temps to go down so fingers crossed.

Any idea what the indoor and outdoor temps were when you noted a 10degC difference at idle? Hopefully they were 10degC apart

60 sounds pretty good to me.

weird_dave · 27 Nov 2011 at 14:00

BurntOutMutha said:
Yes i suspect so, one of my cores has already min temp'd at 1oC so i'm expecting trouble

If the core is reading that, what's the temp outside? Must be sub-zero?
Got any way of measuring temps of stuff? It'd be interesting to know the temps of various parts of the loop.

BurntOutMutha · 27 Nov 2011 at 14:26

Dave - The coolant loop has A/freeze in it so shouldn't freeze regardless if the rad it's in is surrounded by a block of ice. I hear what you are saying about the water pool that the rad is going to sit in will warm up over time, just bear in mind that it's UK outside I'm talking here so that heat should rise out of the water pretty darn quick. No idea on the temps readings that you asked for sorry, all I know is that the 2600k/5Ghz now idles at 18c whereas with a PC 240 rad with 2 YL's at max it never got below 27. I Do know that when I got the 1c read (this was a min read), the outside temp was 7c. Thanks for the tips mate

weird_dave · 27 Nov 2011 at 22:07

Antifreeze, that's a very good point!

I'm a little confused as to how you got below ambient, have I missed something?
I'm still looking at a way to dump the heat into a pond without any risk to the fish, stainless steel heat exchanger is as far as I've got....

BurntOutMutha · 27 Nov 2011 at 22:57

You aren't missing anything. To be honest, I know that the theory says that I could not get below ambient with a passive, but it happened. All I can tell you is that 1c reading was a bit of a shock to me also, but I verified the temps with 2 programs. I do have speedstep on so it's not at high volts all the time and it's very windy where the rad is. My rig is inside a well insulated log cabin which is normally pretty warm (thermostatic heating) so I also am at a loss.......

Jokester · 27 Nov 2011 at 22:59

It's probably the sensor going out of calibration due to it being at an abnormal temperature.

BurntOutMutha · 27 Nov 2011 at 23:06

Possibly....regardless, it's been a successful change and I'm a lot happier with my 5.5ghz benching temps

NasherUK · 28 Nov 2011 at 13:26

Remember not all plastics are able to hold water for long periods, depending on the quality. Eventually the plastic will degrade, mix with the water and split. Being warm most of the time will only make it worse.

BurntOutMutha · 28 Nov 2011 at 16:10

Nasher - What plastic are you referring to ?

weird_dave · 2 Dec 2011 at 17:36

So, to get better clocks, I need a log cabin on a windy hill, very interesting

BurntOutMutha · 3 Dec 2011 at 17:31

Mother nature

sunama · 3 Dec 2011 at 17:48

Just for reference, I have been using a small plastic container as my reservoir, for the last 10-odd years. There is not a hint of any degradation.

BurntOutMutha · 10 Jan 2012 at 13:14

So much for the harsh winter I was looking forward to

Carl

Zack101 · 10 Jan 2012 at 18:28

So what sort of temps are you getting now?

BurntOutMutha · 10 Jan 2012 at 21:11

According to the BBC it's 10c outside, inside the cabin it is 17c. After about an hour of benching in 3DMark11 / Vantage, still at 5Ghz / 1.475v I'm getting an idle average of 18c / Max average of 59 and min readings of 8c

Carl