I have seen small peltier elements for ~ £8/$12.
Hang with me for a sec while I run a physics experiment by (it'll be germane, I promise)
Take two cups of tea (same qty and same temp - and hot)
Take two small containers of milk/cream/whatever (same qty and both room temp)
Pour one milk into one tea.
Wait 5 or 10 min.
Pour the second milk into the other tea.
Which one is hotter?
If you said "The one I poured into first", you're right - and you understand that the greater the temperature differential the faster the heat transfer (first cup started out cooler, so slower transfer).
OK - so back to case cooling: If you're going to run a TEC, you want the cool side as temperature-different as possible (for heat transfer efficiency).
This is why I was proposing the cool side be somewhere high in the case.
Your TEC will be much less efficient cooling room-temp air.
BTW, if you're just trying to get your CPU down to reasonable temp with as little fan noise as possible, I'd suggest water cooling without
There's no condensation to deal with and very little noise. If you use something like a "slantfin" baseboard heater unit as a passive radiator, you might
be able to do without a fan at all. I'm using a BlackIce radiator mounted so that my 120mm case exhaust fan blows through it. I've got the fan throttled back to about 950~1000RPM and it doesn't make much noise (under ambient where I am - so effectively silent/unmeasureable). My case temps run about 28C and my processor (Ath 2100+) at 38C at idle or as hot as 42C when running SciSoft Sandra CPU-test continuously (AKA "burn in") for a couple of hours. I'd run it overnight, but I'm running a web server (family/community photos, mostly) and IIS gets um... unresponsive when I'm running these tests...
Oh - I'd also suggest that those $12 TECs won't actually move enough heat to matter much anyway (but they also don't draw enough power that you need a dedicated power supply, so they'd at least be cheap to play with. BTW (and !WARNING!
) read up on TEC before you get tempted to sandwich this between your heat sink and your CPU (just to see...). If the TEC isn't rated for the heat output of your CPU, it's actually worse
than no TEC. You can fry your CPU fast
. I would guess
the $12 TEC is about a 20W one - and you'd need about 75~100W.
And you're totally right about 2 160mm fans not belonging here - (unless they're turning under 1000RPM, I guess...