# Anybody do any peltier staking? -you know a Cascade?

#### A-Bomb

##### Registered
I have 3 50Watt, one 80W and a 156W peltiers. Anybody ever try a staking the 156w under a 50W? Mabe I should tell you how it goes--- Stop me if you think it's a bad Idea.
Water- 10 Gal fish-tank
DangerDen Copper maze
one 156Watt. (on 12Volt and -5 ground)
one 50Watt.
Copper Cold plate
Duron 800
Radio shack Thermal Greese in between each peice. Using wire-ties as a Vice.
A-Bomb

Correct me if I'm wrong, but shouldn't a TEC on top of another TEC be stronger than the one below it?

Peltier stacking is a very BAD idea! Your second peltier would need to be HUGE. So huge that even watercooling would not keep it cool.

Let's go through some simple math (we will keep this math nice and fuzy for the G.W.B fans out there):

In order to keep a CPU nice and cool, you should have the first TEC pump about 2 times the heat as the CPU puts out (in order to get as close as possible the the DeltaT). In order to keep the first TEC nice cool you want your second TEC to pump 2 times the heat as the CPU and the first TEC generate.

Lets use a P3 700@933 as our hypothetical CPU. A P3@ 933@ 2V cranks out 32.5watts.

C=CPU waste heat=32.5W
t=First TEC
T=Second TEC
F=combined heat output from all sources

t=2C=65W
T=2(t+C)=195W
F=T+t+C=292.5W

Try and find a compact cooling solution to take care of 292Watts of heat

2 times

Hey-- Do you know where I could get a small freon coil?
Is using a -5 for the Power supply ground with the 12 a good way to power a peltier @17volts?

I don't know fussy math yet, I blame it on my boring Algebra 2 teacher giving me D's. Anyway who needs math when George Walker Bush could throw Einsteins greatest daunting intventions around like toys, if you took his oil away.
What is a good cheap way to chill a liquid? ------NO B.S. answers like "just fill your tank with Ice"

A 156W Peltier is much more than 2 times as a 50W- so If i could chill my water/liquid somehow--- would I be better off with or without the extra 50W?
A-Bomb

A single 156W peltier(used with water cooling) will do a peachy job keeping even the hottest CPU nice and cold(below zero anyway).

I would tend to agree with Mr. Evans on this one if you can power that peltier @ 17V then you should go with the 156Watt peltier but everytime I have tried to do it my PSU's always automatically shut off because of a power overload. You'll probably only make it to 12V would be my guess. I am going to be testing a cascade soon i have some 36's and a 72 laying around doing nothing and a couple waterblocks so I'll see how it goes. Well hope it works out for ya.

-dasouthernocer

You can use the 156 on the cpu and then use the extra pelts to cool the water in the tank...tho i dunno how that would work with a 10 gal tank

Definately DO NOT try to attach the peltier to the -5V line of a power supply - doing this to fans is fine because they draw very little power, but a peltier will *always* overload the -5V line.

Regards,
Dave

And possibly make a pretty light show for all of us to gaze at with awe... ;D Just Kidding man, I agree with Jeff, you could have a thermal runaway...and that could be bad...REAL bad, unless your rich of course, and if you are, man, my birthday is coming up in 4 months...sure could use some cash...old pal. Not only that, could you imagine what kinda JOB it would be to seal all of that mess up...oh man, I wouldn't even wanna try it. I'm already having enough trouble withOUT the use of solid state cooling devices....