Conduction of TECs

cougem · 06-20-2004, 04:01 PM

Hi, I'm considering getting an 80W TEC for my graphics card, but I was wondering what performance would be like if I wanted to turn it off for some reason? I mean are TECs good at conducting heat when off, and so I wouldn't loose to much performance? Or would I lose a fair bit? Or are they essentially insulators and I'd get crap performance and the core would go through the roof?

Also, if I had it in series with an MCW-6002 running of an MCP600 w/ 2 single heatercores, how much would it raise the water temps by, I mean how much would it add to my processors heat? Would I lose a fair amount of O/C-ability on the CPU's behalf?

Groth · 06-20-2004, 04:30 PM

By design, TECs are poor heat conductors, to minimize the heat that leaks back from the hot side to the cold side. An unpowered TEC would lead to a meltdown.

The extra heat from the TEC/GPU will raise your water temperatures (and thus CPU temps) by anywhere from none to a whole bunch.

That ain't much of an answer, but it all depends on what rads and how much air you're pushing through them.

I have two six by nine heatercores with low-speed fans. With a heatload of about 120 W, water temps are 2.5 C over ambient. If I added a 100 watts of TEC heat, I'd expect water temperatures of 2.5*(220/120)=4.6 C over ambient.

cougem · 06-20-2004, 04:51 PM

Ah right, so how much heat would an 80W tec put out? I've got pretty low speed 120mm fans on single heatercores, with 78CFM each, and only 25mm thickness. That's at 12V, I usually run them slower though.
This is them on:

And in my rad box:

BUT my system aint up yet so I don't know my water temps....with an 80W tec how much do you think my A64 would raise by temp wise?

Groth · 06-20-2004, 05:44 PM

Pulling number from the air...let's call your pair of small rads equal to one of mine. Maybe, 80 watts for your CPU, so around 3.5 over ambient for the water with just the CPU. Add in 50 W for a GPU, about 5C over. 100 W to power a TEC puts the water ~9.5.

My tea leaves predict a 6° hotter CPU from a pelted GPU block. :shrug:

By the way, your box looks a lot cooler than my cardboard-shrouded heatcores sitting on the floor.

cougem · 06-20-2004, 06:19 PM

Thanks for the help Groth

I think I'll avoid the TEC. It'll mean I can run it quieter with lower RPMs, and show off a bit more with my temps

And thanks for the comments on the box, it's my first mod really, and I'm happy with it.

06-20-2004, 04:01 PM	#1
cougem Cooling Savant Join Date: May 2004 Location: Cambridge Uni Posts: 176	Conduction of TECs Hi, I'm considering getting an 80W TEC for my graphics card, but I was wondering what performance would be like if I wanted to turn it off for some reason? I mean are TECs good at conducting heat when off, and so I wouldn't loose to much performance? Or would I lose a fair bit? Or are they essentially insulators and I'd get crap performance and the core would go through the roof? Also, if I had it in series with an MCW-6002 running of an MCP600 w/ 2 single heatercores, how much would it raise the water temps by, I mean how much would it add to my processors heat? Would I lose a fair amount of O/C-ability on the CPU's behalf?

06-20-2004, 04:30 PM	#2
Groth Cooling Savant Join Date: Mar 2003 Location: MO Posts: 781	By design, TECs are poor heat conductors, to minimize the heat that leaks back from the hot side to the cold side. An unpowered TEC would lead to a meltdown. The extra heat from the TEC/GPU will raise your water temperatures (and thus CPU temps) by anywhere from none to a whole bunch. That ain't much of an answer, but it all depends on what rads and how much air you're pushing through them. I have two six by nine heatercores with low-speed fans. With a heatload of about 120 W, water temps are 2.5 C over ambient. If I added a 100 watts of TEC heat, I'd expect water temperatures of 2.5*(220/120)=4.6 C over ambient.

06-20-2004, 04:51 PM	#3
cougem Cooling Savant Join Date: May 2004 Location: Cambridge Uni Posts: 176	Ah right, so how much heat would an 80W tec put out? I've got pretty low speed 120mm fans on single heatercores, with 78CFM each, and only 25mm thickness. That's at 12V, I usually run them slower though. This is them on: And in my rad box: BUT my system aint up yet so I don't know my water temps....with an 80W tec how much do you think my A64 would raise by temp wise?

06-20-2004, 05:44 PM	#4
Groth Cooling Savant Join Date: Mar 2003 Location: MO Posts: 781	Pulling number from the air...let's call your pair of small rads equal to one of mine. Maybe, 80 watts for your CPU, so around 3.5 over ambient for the water with just the CPU. Add in 50 W for a GPU, about 5C over. 100 W to power a TEC puts the water ~9.5. My tea leaves predict a 6° hotter CPU from a pelted GPU block. :shrug: By the way, your box looks a lot cooler than my cardboard-shrouded heatcores sitting on the floor.

06-20-2004, 06:19 PM	#5
cougem Cooling Savant Join Date: May 2004 Location: Cambridge Uni Posts: 176	Thanks for the help Groth I think I'll avoid the TEC. It'll mean I can run it quieter with lower RPMs, and show off a bit more with my temps And thanks for the comments on the box, it's my first mod really, and I'm happy with it.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)