TEC Question

[Ranger2992]

Right now I am running a swiftech with an 80W TEC on my VC. I haven't volt modded yet and I am able to hit 510 on the core. I will be Vmodding the card in a couple of weeks and am wondering if the 80W is going to be enough to keep it cool. I would really like to get above 530 on the core. So with this in mind, I have a couple of questions.

1) I will be using chilled water (I am making a chiller), will the 80W be enough?

2) Should I switch to a 172W to get the higher clocks? This will require me to buy another mean well and probably a different waterblock.

Any opinions or suggestions would be greatly appreciated.

[]JR[]

How cold is the water going to be? If its -20 or below, you may aswell throw the tec away, you will get better temps with just chilled water.

What tec waterblock you got at the minute? The mcw50t will take a 172watt tec no problems, its better than the 80w even at low voltages since the efficency is higher.

]JR[

[Ranger2992]

Yeah i have the MCW50T. I am hoping for -10C or so for the chilled water. To get to 510 on my core with the 80W I fill my Res with ice. I don't know what it drops the temp down to on the VC, but it drops the temp on my CPU using the MCW462UT down to -20C and allows me to hit 4Ghz :D

I am hoping with the chilled water I can get 530 on the core. Do you think it's possible with a Vmod?

[]JR[]

Probably. Ive just ran some simulations of the 80w vs the 172w modules given the same parameters (20c hotside cooling, 50watt heatsource)

80w module
Input power: 79.89watts (4.7amps 17volts)
Total Hotside load: 131.65watts
Object temp: 11.2c

172w module
Input power: 79.48watts (6.1amps 13volts)
Total Hotside load: 132.51watts
Object temp: 4.8c

So for the same power the 172w module is 6.4c cooler. Ill just do it for -10c water, instead of 20c...

]JR[

[]JR[]

80w module
hotside load 133.48watts @ 17v
object temp: -11.4c

172w module
hotside load 134.87 @ 13v
object temp: -19.6c

So starting to pull away even more 8.2c difference.

]JR[

[Ranger2992]

Wow you just plug the numbers into a database and it tells you how it will perform. That's awesome.

Why is it my CPU temp gets to -20C using ice in my Res? Is the 226W TEC that much better? When i use a wattage output calculator it shows my CPU at over 150W at 4Ghz. Add that with the 226W TEC and it's some serious heat going into the water. When I measure my water temp without ice after an hour or so my water temp is a little over 100F yet I am still able to sit at about 3C idle and 10C full load.

I am still trying to figure these damn TECs out :D

[Ranger2992]

Originally posted by ]JR[
80w module
hotside load 133.48watts @ 17v
object temp: -11.4c

172w module
hotside load 134.87 @ 13v
object temp: -19.6c

So starting to pull away even more 8.2c difference.

]JR[

The 80W runs at 13V....I thought the 172W was supposed to be at 17V??

[]JR[]

The 80w and 172w the simulator uses are both 24v. Its pretty irrelevant its the watts that matter ;)

That wattage calculator (if its the one i think it is) is rather inaccurate, I would suggest 125-135watts depending on voltage.

The 220w figure (q) is achieved when dT = 0, i.e where there is no longer a use for having a tec in the system.

100f is 36c? so your running 36c water and getting around 6.5c temps, hmm.

My software tells me a 220w running @ 12v to get 6.5c would be cooling an 85w heatload.

]JR[