172 watt peltier enough to cool A64?

[UnderWare1213]

I'm thinking of purchasing a Maze 4-1 CPU block and putting on a 172 watt peltier, but I was wondering if that was enough to cool an overclocked Athlon 64 3000+. What temperatures can I expect?

I also have a Maze 4-1 GPU block with a 110 watt peltier on my Radeon 9800. Can these two run on a 320 watt Meanwell PSU fine?

What if I changed the 172 watt peltier on my CPU to, let's say, 226 watt. Will I notice a nice drop in temperatures? Then I will be over the 320 watt limit on the Meanwell, but is that okay?

I appreciate the help, thanks!

[yaboc]

it's ok to run 172 on meanwell + it can handle 226 just fine. running both 172 + 110 can stress the psu a little bit. for a64 i think 226 is better. what i would do is to upgrade the CPU to 226 and run the 110 from second PSU (atx, dedicated). temps depend on max OC, inline or paraller loop (cpu+gpu or cpu - gpu or gpu -cpu).

[saaya]

and it also depends if your running xp32bit or 64bit.

a64s run a lot hotter on a 64bit os'es

[UnderWare1213]

Oh, I didn't know that was a factor. Thanks for the heads up, but I'll be using 32-bit more.

How much of a performance hit will I take by running the peltiers at 12 volts instead of what the specs say, 15 volts? Is it worth spending extra for a dedicated PSU when I can get a cheaper, high-amperage ATX PSU? The Meanwell 320-12 only goes up to 13 volts, though. I think that is not worth spending extra, or am I mistaken? Are there better choices for power supplies?

Perhaps there's a way of modifying an ATX PSU to run over-spec'd on the 12v rail? Any info on that?

About the water loop. For now, I would run it inline, going from my submerged Hydor L30 to the radiator, then to the CPU block, then GPU then back into the reservoir. I'm not sure if a dual 120mm heatercore will handle the load, however. I am considering purchasing another radiator of the same size. Is another heatercore necessary to handle the load?

Or I can buy another pump as well as another radiator and just have two seperate loops, sharing the same reservoir. Better?

Another idea could be a Y-adapter coming from the radiator. One tube going to the CPU and another to the GPU. Then connect the two back into another Y-adapter and return that back to the reservoir.

This is kind of complicated for me so I am thankful for all your help.

[yaboc]

i don't know how much of a performance hit you'll take by running TEC at lower volrages, but you will definately not be using full potentail of TEC. About the psu i don't know i never used ATX PSU to power tec, other than 80W on my MCW50-T. I have 120 dual heatercore and the temps are ok. i still need to change the tubing (been busy lately), because the one i'm using now is bad. i'm running CPU-GPU in line and with my bad tubing i'm getting 9C (3200+ speeds , hopefully better tubing will fix the temps a little bit). you can experiment with different loops paraller, inline etc and see which one gives you the best temps. getting second rad + pump not a good idea. just put a secon rad in the loop and the temps will drop.

[saaya]

id actually recommend to run tecs at less thna their rated volts.
12v is exactly the sweet spot for a 15v tec, where it runs best. it removes only slighly less heat (around 10W) but creates less heat itself.

so while you remove 10W of heat less, the tec produces less heat, the hot side gets slitghtly colder, wich results in a slightly colder cold side, so the temps on the cold side stay pretty much the same but you have to remove less heat.
ive never tried this myself though, i just kept hearing it from people who played a lot with tecs.

keep in mind though that lower volts means it will pull more amps!

yes atx psus can be used to power the tec, but check is it has enough amps

no i wouldnt recommend using the same res as it would mean the hot water of the tec loop and the cold water of your first loop would mix and kill the tec advantage pretty much.

[UnderWare1213]

Okay, I think I have made my decision to run the 226 watt peltier off a Meanwell PSU and the 110 watt peltier off either my computer PSU or a secondary ATX PSU, since I don't think a Meanwell 320 can handle 110 + 226, correct?

I have a Thermaltake PurePower 420 which says the 12v rail can handle 18A. It's already powering an A64, Radeon 9800, and two hard drives. Would adding a 110 watt peltier be a bad idea?

saaya - That's an interesting point about the "sweet spots" of peltiers. It makes sense.

yaboc - Yes, I will add a second radiator since I feel that it is much needed. I just hope my Hydor L30 is strong enough. But the blocks I intend on using are not very restrictive.

Thanks for all the responses, guys. Sounds like a new project for me :)

[saaya]

what is the 110W tec rated to run at ?

12v? 15v? 24v?

it will probably pull around 9amps on the 12v rail... i really dont know how important the 12v rail is for a64s and how much they load it... the 9800 only uses the 5v rail, so that doesnt matter.

i think it will be ok, but if your 12v rail is already low (11.5v) or drops to 11.5v or lower when running the tec and your systen i would use an extra psu for the tec. any cheap 300W psu should be fine, there are some on ebay for 10$ here...

[UnderWare1213]

Here's the 110 watt peltier: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=3829237078&ssPageName=STRK:MEWN:IT

My 12v rail is stable at about 12.2v so I guess it should be okay. I have a 350 watt ATX PSU here, but I just thought it would be more convenient by not using another seperate PSU.

[saaya]

their termal specs keep confusing me... +180C? afaik tecs die pretty fast if the temp on the hot side rises above 70C.

180C makes no sence, at above 100 the plastic insulation on the cables would already start to melt...

since they claim it works as low as -60C i guess those are the pure theoretical values as its proven that tecs stop working below -45C. so i guess the temps are the extremes the tec can "survive" but its not supposed to be working at those temps.

it should be fine on your main psu. as i said, try it. if the wires of your psu run hot, the system gets unstable, the rails fluctuate or the air comming out f the tec is very hot use the extra psu.

[UnderWare1213]

Now a question about order. I plan on having this configuration:

Pump (submerged in reservoir) --> 1st Radiator --> CPU Block --> GPU Block --> 2nd Radiator --> Back to reservoir

How does this sound? Better than having the radiators consecutively placed?

Pump (submerged in reservoir) --> 1st Radiator --> 2nd Radiator --> CPU Block --> GPU Block --> Back to reservoir

[=[PULSAR]=]

Just a quick question this is a little off topic. The 172W TEC he is talking about, it runs best at 24V so how would I go about hooking a power supply up to it? Could I connect two meanwells in series?

[saaya]

underware, i dont know how restricitive your rads are, but if they arent especially restricitve it should be fine. changing the position of the rads in the loop wont make a big difference, in theory the best would be to have the second rad between the cpu and gpu, but thats really just theoretical and i doubt you could meassure the difference in temps ^^

some corrections :D

1st a64s dont run THAT much hotter with 64bit, probably around 10-15W.

2nd running tecs at less than their rated max voltage makes them more efficient if your cooling of the hot side is limited, if not then its best to run them at full volts to pump as much heat as possible from the cold side of the tec to the hot side.

3rd the difference between 15v and 12v is not 10W, it depends on the tec and is around 10W for an 80W tec and around 20W for a 172W tec etc...

4th the tecs CAN take more heat but it limits their lifetime quite a bit and i dont recommend running tecs with the hot side at or above 60C.

5th the cable insulation can probably take more than 100C, probably around 120-150C depending on the plastic used, but it would start to get liquid or corrode at 100-120C so its kinda weird to see the tec rated to run at those huge temps. i think they mean the tec can survive those temps, but not while its powered.

pulsar, there are 170W tecs with 24v vmax and 15v vmax. even 12v vmax i think.

yes two psus can be used to reach 24V, even two at and atx psus can be used to reach 24V. i posted a link to a guide how to do it a few weeks ago, use the search function and im sure you will find it :)

to reach 24v you will need to do some soldering and i would use only two psus of the same series! but its cheaper than getting a 24V psu if you already have 12v psus :)