Not happy with temps under water setup

[CustomBuild]

I am running a CPU only loop. I initially was using a GTS120 and a TDX with the stock (#1) nozzle. I was getting +7-8C detla (from 20C room temp) as measured by Core Temp and MBM. Under load at 3GHz I was getting ~+19C according to MBM and ~+21 according to Core Temp. I saw some posts that indicated people could get +6 at idle and ~+13 load.

 

I wanted to push my temps a little lower for more OC attemps over 3GHz. I "upgraded" to a GTX240 and the #4 nozzle in the TDX. I was expecting a 3-5C change, but to my surprise I can't see any difference in temp delta. I idle where I idled before and under load (@3GHZ) I sit right at ~41C (+21).

 

With the larger radiater, reduced pressure loss from the rad, and the smaller CPU block nozzel, I am not quite sure why I don't see any benefit. I also see no difference if I run the rad fans at 50cfm or 80cfm.

 

That tells me it is not a heat capacity issue, but a heat transfer issue. I am afraid it has to be at the CPU itsself and my heat transfer between the die/IHS/and TDX is the limiting factor At this point I realy don't want to remove the IHS. Oh and I used Ceramique (dab in the middle).

 

I don't have any other ideas at this point. Are my delta's pretty normal, or should I really be able to hit someting around +6 idle +13 load (1.48-1.5V range)?

[radodrill]

My guess would be a bad contact between the WB and the IHS. Also, try switching to Arctic Silver 5 as it has much better thermal properties than the Ceramique (might be the source of the problem).

[WintersFury]

AS5 may help, but I've only found there to be a 1c or so difference between the two.

 

It does sound like the IHS isn't thermal compounded to the core very well to me as well. So you may have to pop the top to get the temps down more. Also your ambient may just be hot? As you are in Texas and I know it gets pretty toasty down there.

[watsonte]

are you pulling or pushing air across the radiator....? And do you have any other way to monitor your temps....

 

Granted no matter what you use every program will still never be entirely accurate....I say try a different temp program and see if they show the same temps...

 

Also what are your ambient temps like? Ambient temps dictate how well your system will perform...

 

And really your deltas seem pretty normal to me....I have built 4 rigs with watercooling and normally I see a difference of 10-12 C from idle to full load depending on the voltage

[Thraxz]

And really your deltas seem pretty normal to me....I have built 4 rigs with watercooling and normally I see a difference of 10-12 C from idle to full load depending on the voltage

 

Unless your on a heavily OCed C2D :eek2:

[CustomBuild]

are you pulling or pushing air across the radiator....? And do you have any other way to monitor your temps....

 

Granted no matter what you use every program will still never be entirely accurate....I say try a different temp program and see if they show the same temps...

 

Also what are your ambient temps like? Ambient temps dictate how well your system will perform...

 

And really your deltas seem pretty normal to me....I have built 4 rigs with watercooling and normally I see a difference of 10-12 C from idle to full load depending on the voltage

 

I actually push/pull, but I think that is probably overkill.

 

My ambient (room temp) is 20C.

 

It may be my delta's are normal. It is possible the posts I saw with lower numbers were naked CPUs, I don't remember.

[watsonte]

I suggest just pulling cool air across the radiator...airflow withing the case will increase temps a little so you will still need to maintain good airflow across your motherboard...

[General Septem]

Try an accelerator nozzle for the TDX perhaps? I'd probably go lidless if I were you though.

 

Wait, never mind, I didn't see you'd tried that already.

[radodrill]

Try an accelerator nozzle for the TDX perhaps? I'd probably go lidless if I were you though.

 

Wait, never mind, I didn't see you'd tried that already.

 

At this point I realy don't want to remove the IHS.

 

His CPU still has it's "hat" on.

 

You probably won't see as much of a gain going lidless as with a lot of older CPU. C2D's have the IHS soldered onto the die so that would allow excellent heat transfer (unless it's a poor solder joint). Heat transfer issues are probably between IHS and WB rather than between Die and IHS.

[slow&#39puter]

Do you have the rad inside the case or outside? If inside, improve case airflow and flow across the rad. Also, I have found out that brand name rads are not as effective as heater cores. (How? Lots of observations from posts like yours)

 

Another thing, what pump are you using? You sure you got proper flow? What size lines? You might be either moving water too fast (not enough time to transfer) or too slow (heat saturation). No kinks on the lines? Air purged from the rad and TDX?

[radodrill]

Do you have the rad inside the case or outside? If inside, improve case airflow and flow across the rad. Also, I have found out that brand name rads are not as effective as heater cores. (How? Lots of observations from posts like yours)

 

Another thing, what pump are you using? You sure you got proper flow? What size lines? You might be either moving water too fast (not enough time to transfer) or too slow (heat saturation). No kinks on the lines? Air purged from the rad and TDX?

 

The D5 in his sig indicates that he's using 1/2" ID tubing.

The fact that he switched from a 120mm Rad to a 240mm Rad without any improvement shows that it's not an issue of heat transfer from the Rad. As a result the issue lies at the CPU/WB interface.

Other than that, the only possibility is that his OCed CPU just runs very hot under load.

[politbureau]

Like Watsonte, I think your temps are fairly normal, but you could probably pull a few degrees off your idle and load temps with some tweaks. I'm not sure what would give you the best results in your situation, but here's a few things I thought of which might help.

 

1. AS5 vs Ceramique is another argument altogether (I like Ceramique, personally), but the critical thing is application. To make sure you are applying it correctly, try putting a small dab in the center of your IHS, then apply the block as you normally would. Now carefully take the block off and observe how the compound has spread. It should look even and nearly transparent, around the size of a quarter. Keep working on this technique until you have it down and can be confident in your application.

 

2. Your loop should look like this: [ D5 > Rad > Block > Reservoir > D5 ]. Obviously if you don't have a reservoir, take that out of the equation. This setup is becuase the D5 dumps a fair amount of heat into the water at full power. You want the rad after the pump and before the block to remove as much of this heat as possible before it hits the CPU. BTW, I've always found that a reservoir, besides making filling/bleeding 1000x easier, actually pulls an extra degree or two from the loop. FYI.

 

3. Push/pull is a bit overkill, IMO, and as mentioned I would just use a straight pull config. Make sure the fan is well sealed to the rad (or use a plenum/shroud) and if the rad is inside the case, ensure it is sealed such that it's only pulling cool air from the outside.

 

4. Nozzle #4 gives me the best results without being too restrictive. I actually saw a slight temperature increase with nozzle #5 on my D5, most likely due to pressure drop.

 

5. A 240mm rad is overkill for a CPU-only loop, and I am not surprised you don't see a temperature drop. Most people forget there is a point where you simply cannot cool the water any further. Water cooling is still based on air, afterall, and the ambient temperature and humidity play the largest roll in what your overall temperatures will be.

 

6. What coolant/additive are you using? I use the typical Zerex + de-ionized water, which I find gives the best overall results. From past experience, I personally think all UV/dye additives have a negative effect on performance.

 

7. Did you get all the air bubbles out of the loop before you installed it? I gently shake and move all the components around (flip over, etc) during leak testing to get ever last bit of air out before I finalize the installation. This will have a huge impact on performance if not done correctly.

 

8. I had nearly the exact same loop as you before. Here's my setup and what the temperatures looked like for comparison:

 

- Expert + Opty 165 (IHS intact)

- D5 + BIX120 + 0.8L Reservoir

- TDX + Nozzle #4 + Clearflex 1/2"

 

- 3GHz @ 1.52v

 

- Ambient: 21°C

- Idle: ~26°C

- Load: ~37°C

 

With that setup, I saw almost exactly 5°C above ambient at idle, and 11°C above idle at load.

 

When I upgraded to the GTX120 and MCP355 (w/ PTS top), I saw the same idle temps, but my load temps came down 2 degrees (idle + 9°C).

 

Adding the GTX240 didn't reduce temps at all. I saw the same delta over ambient and idle, but the larger rad allowed me to add a GPU block with no impact on CPU temperatures.

 

Hope this helps!

 

P.S. If you're looking for an inexpensive waterblock upgrade, I've found the Cooltechnica Whitewater block ($34 on sale, here) actually performs a few degrees better than the TDX. Bear in mind it is a dual outlet design, and as such will neccessitate a 'Y' adapter, a couple extra lengths of tubing and a few more clamps. However this design works fantastically well with the DD 5.25" HDPE bay reservoir ($8.99 on sale, here), which has two inlets and one outlet.