Water cooling tips

[madocks]

Firstly basic rig info...............

NF7-S (Rev 2)
1700 DLT3C
1 Gb Generic ram

Now water cooling info............

120:1 black ice xtreme rad
Eheim 1250 pump
Custom made cpu block, lapped to grade 1200 paper (Made it meself, and proud too)

Flow = Pump - Rad - Res - Block - Pump

OK here the temps..........

All temps taken with built in temp probe on thermaltake case (probe stuck underneath processor), water temps taken with fish tank thermometor

1700 @ 2.2 gig idle = 36 / Load = 38 (200X11 with 1.7 vcore)
1700 @ 2.4 gig idle = 40 / load = 46 (200X12 with 1.75vcore)

When clocked to 2.4 gig water temp in res rises to 30 degrees, I made a point of having the res after the rad, is 30 degrees water ok?

Any tips for reducing the temps? ( i want 2.5 / 2.6 if poss)

Pics of case and setup here ;

http://homepage.ntlworld.com/bibblem/rig1.jpg

And here ;


http://homepage.ntlworld.com/bibblem/rig2.jpg

[Atomic]

I'd change:

Dump the elbow connections on CPU Block and put on straight ones.
Move the pump further away from the fan on the rad, its blocking airflow.

Also thats quite small tubing for a beasty pump too!

[madocks]

I'd change:

Dump the elbow connections on CPU Block and put on straight ones.
Move the pump further away from the fan on the rad, its blocking airflow.

Also thats quite small tubing for a beasty pump too!

The elbow connectors have gotta be there, or i end up with loads more tubing

Good idea on the pump, perhaps ill chuck another 120 fan onto it while im there

Aye, small tubing, it has an inside wall of 10mm, which seeing as the reservoir i bought only has 12mm holes in it, which after a thread has been inserted it reduces the hole to 10mm i didnt see a problem

[daniel_owen_uk]

Definitely change the order, you are dropping flow rate to cpu block, first of all you go to rad first (which some like), but the main prob is you are going to res b4 cpu block, the means the only pressure is gonna be from the pump sucking towards the block (not ideal).

Change it to - pump rad cpu res (if you must have rad b4 cpu).

[Atomic]

The elbow connectors have gotta be there, or i end up with loads more tubing

Elbow connectors are a good way to kill the flow. The water is hitting a wall then being redirected. Shame you have to keep them really.

Definitely change the order

Change it to - pump rad cpu res (if you must have rad b4 cpu).

Missed the order there. Definatly change it to the above!

[megah0]

consider having - Pump - Block - Rad - Res

[skattrd]

Isn't it best to have the block directly after the rad .... the water temp is lowest after it comes out of the rad, correct me if I'm wrong.

[madocks]

Definitely change the order, you are dropping flow rate to cpu block, first of all you go to rad first (which some like), but the main prob is you are going to res b4 cpu block, the means the only pressure is gonna be from the pump sucking towards the block (not ideal).
.

Just been thinking, lets say that this pumps shifts 1 litre of water a minute (It does lots more but for test ), whether a cpu block is after the pump or before the pump, surely 1 litre every minute will pass thru the cpu block, ok it wont be under as much pressure, but.............. it still has the same flow rate thru it.

Whats pressure got to do with it?

[daniel_owen_uk]

Good point, I was just always under the impression that highest flowrate came just after pump, (no restrictions).

[Butuz]

The flowrate is the same throughout sureley.

Beans as theres no air in the system, all that is there is water and the same amount of water comes out of the pump as what goes in, and at the same speed.

That is unless my brain has failed entereley. I wouldnt rule that out tho to be honest.

Butuz

[turkster]

Can you measure the temperature of the water coming from your rad? That is the important thing. If you hope to get lower temps on your block then your rad will have to be up for the job. No amount of flowrate/pressure/pumps or tubing are going to help you if your rad cannot cool the water enough.

[madocks]

Can you measure the temperature of the water coming from your rad? That is the important thing. If you hope to get lower temps on your block then your rad will have to be up for the job. No amount of flowrate/pressure/pumps or tubing are going to help you if your rad cannot cool the water enough.

The reservoir comes after the rad in the system and the water temps are measured from the reservoir with a thermometer

[turkster]

The flowrate is the same throughout sureley.

Beans as theres no air in the system, all that is there is water and the same amount of water comes out of the pump as what goes in, and at the same speed.

That is unless my brain has failed entereley. I wouldnt rule that out tho to be honest.

Butuz

Well roughly speaking yeah. The same amount of water goes in as comes out but there is a pressure drop (friction/resistance) over the circuit (hence the importance of a pump with reasonable head of pressure to maintain flow through the circuit). Some parts of the system such as the water block and the rad cause most of this pressure drop. By Bernoullis equation any drop in pressure=an increase in flow and vica versa so the flow rate will actually increase slightly in certain areas.

[turkster]

The reservoir comes after the rad in the system and the water temps are measured from the reservoir with a thermometer

Oh sorry missed that. Well if your water is at 30 then a temp of 40 on the chip at 2.4ghz doesnt seem too bad. Your best bet would be to try and get your water temps lower by using a bigger rad or more powerful fan etc.

With a massive passive rad I manage to keep my water temps to within a few degrees of room temp and my proccesor (xp2500@2.3ghz) a few degrees above that ie in the region of 25-29C.

[madocks]

Spotted a leak from the cpu block, sorted it now.............While i was there, did a bit of lapping and replace the arctic silver and rerouted some piping, also added another 120mm fan to get water temp lower

New Sequence: Pump -> RAD -> CPU -> RES -> Pump

Results of makeover

Hard to believe but at 2.4 gig stable temps have dropped from 46 under load to 41

Temp of water has dropped to 28, bear in mind, now the res is after the cpu so is at its hottest , whereas before it was after the rad so it was at its coolest. I think the extra 120mm fan has made a big diff.

Mega happy

Roll on 2.6