HD7990 getting to hot (with Water Cooling)

[antraxo]

Hi...

Ill got today my 2 x Gigabyte HD7990 incl. Water Cooling System etc...
Now its my first Water Cooling System and i am not realy PRO in this..

If ill start my miner, one of the 4 CPUs gets to over 100c heat ... the others stay at 45c.
Ill have touch the water and its cold... The Tubs are cold to.. Like there is no pasing hot water.

I cant change the Voltage etc... becouse it blocked.

But normaly with water cooling there should be not getting to 100c ill think...


My Settings:

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer --scrypt -o stratum+tcp://pool -u worker -p pw -I 13 -g 2 -w 256 --thread-concurrency 8192 --gpu-threads 2 --gpu-powertune 20


Thanks!!!

[antraxo]

Could it be that the way for the Tubes are to long?
Ill use extern Water Cooling becouse each 7990 has one radiator with 3 x 120.

[virtualaddict]

I don't know anything about water cooling but I know if you're hitting 100c, then there must be a gap between the part that needs to be cooled and the part that does the cooling.

[Nullu]

Cold water in the tubes implies the heat transfer isn't getting from the GPU to the water block. Did you apply the thermal paste to the GPU? Did you apply the thermal pads correctly to the block for the VRM modules?

Check to see your pump is actually running. Another possibility is an air pocket trapped in your radiator that your pump can't shift. Give the rad a light shake. You can also tap the reservoir to dislodge air bubbles. You're meant to bleed the air out of the system and let it bed in before running it under load. Also check your reservoir and see if the water level has dipped. If it has, top it up as necessary.

Tubing length shouldn't make a massive difference, but if you've got a weak pump then it may struggle. Post your entire watercooling rig specs and I'll look at it tomorrow. Any pump like a DDC, DCP or D5 should be fine, although a weak DCP may struggle.

[BrewCrewFan]

Cold water in the tubes implies the heat transfer isn't getting from the GPU to the water block. Did you apply the thermal paste to the GPU? Did you apply the thermal pads correctly to the block for the VRM modules?

Check to see your pump is actually running. Another possibility is an air pocket trapped in your radiator that your pump can't shift. Give the rad a light shake. You can also tap the reservoir to dislodge air bubbles. You're meant to bleed the air out of the system and let it bed in before running it under load. Also check your reservoir and see if the water level has dipped. If it has, top it up as necessary.

Tubing length shouldn't make a massive difference, but if you've got a weak pump then it may struggle. Post your entire watercooling rig specs and I'll look at it tomorrow. Any pump like a DDC, DCP or D5 should be fine, although a weak DCP may struggle.

+1
I am going to go with not set properly for 1000.

[antraxo]

Hi,

ill have 2 pumps each with 1250 liters/Hours... So each of my 7990 has his own Pump.
Pump is working becouse its extern water cooling, so ill see the water coming out again.
But ill must say that the water coming not very strong out..

All Paste is done by PROs (Ill got the 7990 already with Paste and Pads mounted my Water Cooling Company).

[xrturbs]

yup try pressing the cooling pad against the gpu , if the temp drops fast it's not seated properly.

[antraxo]

Ill just try to push it against the VGA but the one Cooling Ped is hot (The whole metal).... The other one is cold..

[Skydvr823]

I've seen that quite a bit in the forums. That is why I built mine in a milk crate with a box fan blowing directly on the GPUs which are on risers. It seems to keep them cooler than people post. I've only been doing it for a little over 2 weeks, but temps with over clocking seems to be steady around 75c.

[Nullu]

Ill just try to push it against the VGA but the one Cooling Ped is hot (The whole metal).... The other one is cold..

Either one of two things are happening; that cold block isn't seated properly, or for whatever reason you have a problem somewhere in your loop. My best guess is the card isn't seated properly with the block. Is each card on a separate loop? two pumps would be excessive for one loop. Check to see if any warm air is coming out of the radiators.

I would strongly advise you do not do any mining until you've spoken to whoever set up your system. If your GPU isn't being cooled you could overheat it.

Post exactly what 7990 cards you have, and exactly what waterblocks are on them if you can. A long shot, but I know of a few compatibility issues with some Universal VGA Waterblocks with some 7990 cards because the GPUs sit lower than the bottom of the waterblock, which leaves a gap. It may not be the problem you have, but I'm aware of the issue.

Post the full card name, or see if you can find it on http://www.coolingconfigurator.com/

[antraxo]

Yes, each Card has own loop, with ow radiator, tank, pump etc..

The rare thing is why only 1 of the 2 GPUs are getting hot?


Ill mean 2 x 7990 = 4 GPUs
3 GPUs = Stay at 40-50c
just the 1 GPU go up to 100c...

Ill check for full names now of all the hardware.

Ill must say that the Water Tanks are on same high like the GPUs. But still why 3 GPUs are cold and only 1 get hot..

[Nullu]

Yes, each Card has own loop, with ow radiator, tank, pump etc..

The rare thing is why only 1 of the 2 GPUs are getting hot?


Ill mean 2 x 7990 = 4 GPUs
3 GPUs = Stay at 40-50c
just the 1 GPU go up to 100c...

Ill check for full names now of all the hardware.

Ill must say that the Water Tanks are on same high like the GPUs. But still why 3 GPUs are cold and only 1 get hot..

If it's happening to just one GPU, maybe the thermal paste wasn't applied properly to that one GPU. Anyway. I'm going now. Post what you can and I'll take a look tomorrow.

[antraxo]

My GPUs are:
http://www.gigabyte.com/News/1206/333.jpg

My Water Cooling Blocks are:
http://www.aquatuning.de/product_info.php/language/en/info/p15755_Aquacomputer-kryographics-f-r-HD-7990.html

And ill have 2 Radiators each one with 3 x 120 Fan.

[Nullu]

My GPUs are:
http://www.gigabyte.com/News/1206/333.jpg

My Water Cooling Blocks are:
http://www.aquatuning.de/product_info.php/language/en/info/p15755_Aquacomputer-kryographics-f-r-HD-7990.html

And ill have 2 Radiators each one with 3 x 120 Fan.

I'll look into it tomorrow.

In the meantime contact http://shop.aquacomputer.de/index.php?language=en& - they're usually pretty good. If you're using the SLI/Crossfire Bridge maybe there's an issue there. Explain to them the problem, they may have an idea.

[antraxo]

No body other one has an idea? They are not working today, and tommorow. And ill like to mine with the PC .
Why only one GPU gets hot.. But the whole Cooling Block is hot like fire, but the water is running..