Switching peltiers on/off

[Weee]

So, what I have right now is two 7800gtx that don't like to boot up into windows cold < 0C but I have a hypothesis that I can get them to run if I start cooling after windows boot, I am going to test this first, but how would you recommend I go about switching on/off of the peltiers.

I have two 24V peltiers one for each graphics card, adn I was thinking that I could use use a SPDT switch and just control whether or not the peltiers are on, or just leave it open while I am booting up. with the peltiers off, the cards are still at pretty safe temperatures, but it is a pain to put back in the fork terminals in to the power supply in a fairly crowded case.

Can someone think of a better method for me to shut them off? I'll draw up a quick circuit diagram of how I think it will look. I have two 12V meanwell psus in series to give me 12V and 24V so that is what I have shown in the pictures. here's my beautiful paint artwork

http://i13.photobucket.com/albums/a270/djaziz/301d7a25.png

The meanwell psus are also enabled via relay from the 12V on my psu for "no worries' operation. Although I never leave this computer unattended for more than a pee break while it is operating.

Thanks for advice!

[Holst]

Wont matter much where you put the switch.. i would just switch the PSU wires with a high ampage switch.

Only danger with this is that it leaves the option to forget to turn the pelts on... which might overheat your graphics cards, should you run a game or something GPU intensive.

Im supprised that the pelts cool the cards enough to cause cold bug during boot, my pelt system used to take a good couple of minutes to cool to temperature from cold (warm :P )

You could build a 555 timer to swich a relay that turns the pelts on after its counted so many seconds ... this might be more reliable than doing it manually.

[Weee]

You could build a 555 timer to swich a relay that turns the pelts on after its counted so many seconds ... this might be more reliable than doing it manually.

That sounds easy enough, however it is quite unlikely that I would do any damage to the hardware from 3D where I have the BIOS flashed to right now I also have a temp probe on my front panel that beeps if things go over a set temp as a failsafe, and as I said I don't leave this computer unattended. I have run 3d for a good amount of time with the peltiers off and I still see 20C better than the stock cooling gave me at default clocks/volts on the core.

However, it only has to happen differently once for something dangerous to occur, so I will look into building a failsafe circuit on this guy, definitely something I can handle. The main reason I wanted to switch in the 24V lines instead of the power supply is due to the high AC inrush current when the power supplies are turned on potentially tripping my circuit breaker in my room.

Also at this very moment the cpu has a peltier too, and I want that one to be always on but the graphics ones to be switchable on/off this will change once my single stage phase setup arrives =)

And oh yeah, my peltiers are down within like 1-2C of full on idle temps by the time I get to the part of windows bootup where drivers start to load