TEC help needed.

[Fitseries3]

im not a total noob here but i figured that i would be better to ask before i kill anything.

i have a swiftech MCW6500-T (http://www.petrastechshop.com/swmcthwa1ins.html) and i have been using it for a year now just fine.

it is cooled by 2xpa120.3's which may be overkill but i figured it was best to overshoot than fry a chip/tec. im using a iwaki rd30 as a pump so i have plenty of flow.

the stock pelt in my block is 226watts and keeps dualcores around 8c and quads around 15-19c

i recently bought a 400watt tec and wish to swap them out. the 400watt is the same size as the 226watt tec.

Questions:

1. how do i know which side is the HOT/COLD side of the new TEC?

2. would it be ok to underpower the TEC with a 450watt/20amp psu?

3. will i notice any difference?

4. can i power up the TEC without being in the block?

5. will a 500watt pc power and cooling psu (dedicated)(http://www.newegg.com/Product/Produc...82E16817703015) power this 400watt tec?

6. anything else i should know here?

thanks in advance.

[philbrown23]

rofl

[zipdogso]

rofl

Now,now...titters...that's not the attitude.

Where do we start ??? ahem...

well I will ignore the first 5 questions....

im not a total noob here but i figured that i would be better to ask before i kill anything.

6. anything else i should know here?

thanks in advance.

Your swiftech MCW6500-T has been designed as an off the shelf mediochre unit for people who don't want to mess with the finer details of integrating TEC's into their rig...as a result though what you propose would at first seem quite simple I am afraid it really isn't as simple as you would like.

I assume you are talking about the 400w TEC advertised on ebay...well I am afraid they are a little...um...ambitious with quoting their TEC ratings and if you swap it out with your 226w you will probably find no difference because they are pretty much the same thing.
There aren't any hard and fast rules on how retailers should advertise TEC's power and some of the more unscrupulous ones tell white lies.You need to read all the small print and know what your looking for or ideally get the data from the manufacturer.

Reason for editing - Footnote.
After studying the specs more closely of the Ebay offering it turns out the unit is labelled incorrectly and is in actual a TEC1-12720 NOT the TEC1-12726 they claim and the Qcmax is only 177w so if someone did swap this unit for their 226w they would notice higher temps not lower.

[philbrown23]

i just rofl, cuz he was im'ing me lol.

[Fitseries3]

nope... got it at a local electronics supply shop. it's clearly labled 360-400watts 26amps max. the pelt itself has no indication of hot or cold side and no markings.

so what should i do now?

[HDCHOPPER]

hold in in your fingers and put 5 volts only into it ! it wont take long ,,, so have your other hand on the switch

[zipdogso]

nope... got it at a local electronics supply shop. it's clearly labled 360-400watts 26amps max. the pelt itself has no indication of hot or cold side and no markings.

so what should i do now?

Yes but what wattage is that which is marked ?

A lot of TEC's get marked with Pmax I x V this is totally pointless and has no bearing on the ability of the TEC to cool, it is merely an electrical calculation of the draw from the wall socket.

Some are marked with the QCmax which is the figure that's handy to know, and cannot be determined when there are no markings without knowing how the TEC was made i.e. how many thermocouples it has.

If it is a standard 127 couple unit then the wattage shown is highly likely to be Pmax and you will be in the same boat as my previous post.

If it is a "special" with more couples then it will probably be better than the 226w you have but unfortunately I doubt it.

No numbers on it anywhere is not helpful.
Perhaps you enquire at the shop for some more details...but I know my experience it will probably draw a blank

TEC's never have indication of hot/cold side you to have to find out yourself see HDCHOPPER that's one way. Be sure to mark it as soon as you know. You should also mark which wire you connect to the positive.

Going back to your original questions

2. would it be ok to underpower the TEC with a 450watt/20amp psu?

The "sweet spot" for TEC's is around 70% power there is EXTREMELY little to be gained from using any more. If my assumptions are correct you TEC will be rated at 15.4v. The 12v provided by the PSU will be above the "sweet spot". SEE also question 5.

3. will i notice any difference?

That depends - we have already covered that part you really need to ascertain what TEC you have.

4. can i power up the TEC without being in the block?

You will need to to find out the hot/cold sides it is best to a really low voltage. See HDCHOPPER.
NOTE you MUST not power the TEC without any cooling for very long. By that I mean seconds not minutes. just a few should suffice for you to tell which side is hot and which is cold. If while holding the TEC both sides go HOt....oops you have blown it.

5. will a 500watt pc power and cooling psu (dedicated)(http://www.newegg.com/Product/Produc...82E16817703015) power this 400watt tec?

yes...but I must warn you PCP&C tech guys recommend that with their one rail PSU's you join 2 PCI-E lines together to power the 226w TEC. The problem is there is a fire risk using standard 12v lines and molex plugs (from ANY psu.) which incidently are only rated to take 7 amps ! The PCI_E lines/plugs are rated slightly higher but they still recommend 2 of them !! and just for the 226w TEC never mind higher rated ones.

[Fitseries3]

ok thanks man.

a few more....

is it ok to undervolt/underpower a TEC?

can i cool the TEC with a regular waterblock?

COMPLEX QUESTION...

i have noticed that when i reach the cooling threshold of the TEC that temperatures quickly climb back to high temps. i had my e8600 @ 5ghz and during benching the chip went from 12c all the way to 87c causing the benchmark to crash. i was only using 1.4125v on the CPU. is this because the TEC is underpowered or has it reached its maximum cooling point? the PSU im using is an antec that is 450watts with 20amps on the 12v rail. i know thats not enough now from what was told to me earlier.


EDIT: the model of my TEC is Thermal Enterprises CP1-12726

[zipdogso]

EDIT: the model of my TEC is Thermal Enterprises CP1-12726

what you mean....this is the one you bought from the shop ?
If that's the case then it as comparable to the one in your swiftech unit and with give no noticeable gains.

is it ok to undervolt/underpower a TEC?

See your questions answered in my post above. In a nutshell it should be underpowered. The swiftech unit is.

can i cool the TEC with a regular waterblock?

You could but why not use the swiftech unit? If your contemplating buying an even bigger TEC, bigger physically as well, not using the swiftech unit but instead a waterblock, you will find the contact area on most waterblocks is not large enough. For big TEC's a custom water block is the order of the day.

the PSU im using is an antec that is 450watts with 20amps on the 12v rail. i know thats not enough now from what was told to me earlier.

Unfortunately you did not correctly read was told to you earlier.The PSU was fine.

COMPLEX QUESTION...

i have noticed that when i reach the cooling threshold of the TEC that temperatures quickly climb back to high temps. i had my e8600 @ 5ghz and during benching the chip went from 12c all the way to 87c causing the benchmark to crash. i was only using 1.4125v on the CPU. is this because the TEC is underpowered or has it reached its maximum cooling point?

I am assuming that was a pretty "chunky" OC so the CPU was able to generate pretty hot temperatures quickly.
This is my opinion of what happened :-
possibility one:
Your water cooling of the hotside of the TEC was insufficient.There is a figure known as deltaTmax on most TEC's it is around the 70C mark this is the max temp between the Hot and Cold sides. The coldside became more than 69C different to the hotside and the TEC assumed "no load" and stopped pumping.
possibilty two:
when you started benching the TEC pumped the heat off as the Cpu temp rose from ambient then for some reason in benching the CPU paused, the TEC was pumping heat avidly and then it came to a stop as there was no load. In the next split second the Cpu started again, note at this point the Cpu is probably still warm so the heat rise is faster than that at the start of benching and the TEC couldn't get pumping fast enough.

EDIT
I forget to mention in the first scenario unless the power was cut to the TEC extremely quickly it would of resulted in the death of the TEC. If the TEV survived it's life/reliability will of been severely compromised.

[Fitseries3]

this is what i use to cool the TEC...

http://forums.techpowerup.com/showpo...&postcount=184

http://forums.techpowerup.com/showpo...&postcount=189

http://forums.techpowerup.com/showpo...&postcount=191

the hoses are shorter now and i have the TEC in the loop.

[zipdogso]

Well your watercooling's not a problem...LOL
looks liike scenario two !!

[Vinas]

Could still be the cooling system. If it's reaching 87C then yes, your cooling system can't dissipate that much heat dump. Understand that you are producing an incredible heat load... Maybe it's the pump or the block, probably not the rad though!!! :-) Try benching one core at a time and see if you get similar results.

Edit: I don't think you're overshooting your TEC yet because it runs fine at 100% load for some time. Once your loop heats up the TEC can't maintain the temp differential any longer. The more I think about it I'm leaning toward your pump not moving the heat away fast enough. That huge ass rad is probably pretty restrictive.

[Fitseries3]

im using an iwaki RD30. one of the best pumps with the highest flow available.

[genec57]

In my experience when I tried to take my E8600 past 4.5 the temps went way up as soon as I got past about 1.31 vcore and I was never able to get stability. OTOH, at 4.5ghz my system is stable at 1.27v and idle temps of ~0c and 30c load.
The tec seems to cool fantastically until I reach its limit and then everything goes to hell. I think the problem is tec limitation, not cooling.

[HDCHOPPER]

im using an iwaki RD30. one of the best pumps with the highest flow available.

thought using TEC's you would want lower flow rates to keep the saturation point better but ofcourse the type of block and amount of coolent in the system ect..ect... would drive the exact best flow rate needed per system

my flowrate is very low

[Vinas]

im using an iwaki RD30. one of the best pumps with the highest flow available.

Yeah, sorry I didn't read that you have the iwaki and they are great pumps.

Back to the problem, perhaps your block can't transfer enough heat to the coolant? Do you happen to have an IR thermometer? Some how we need inlet and outlet temps from your block... Maybe even a cold and hot side reading from the TEC? Finally after that we can narrow down the issue. I'm afraid I can't really help unless you can provide some numbers for us.

If the block ends up being the issue you could use a hotplate with two water blocks. Not that you'd want to, but it's been done by others.

EDIT: I was thinking your chip is fine at 1.45vcore because I run mine at 1.58 just fine. I have the e8400 and a 245watt 12v TEC, specs in my sig but pretty close to yours. My heatercore has 4 scythe ultra kaze ~130cfm fans on it. Orthos stays well under 60C after hours of benching and my heatercore pours out heat.

[Fitseries3]

inlet is 32c and outlet is 37c on the block.

i just ordered a meanwell 15v 240watt psu that i plan on running ~12v or more. should i run my block at 15v? i think thats where it actually cools 240watts.

i calculated arou 160watts of heat at 5ghz with my e8600 so i dont know whats going on here. im thinking it has to do with a lack of sufficient power.

i have 6 ultra kazes on my 2x pa120.3s and im running them at 2100rpm.

[Vinas]

Your cooling system is quite nice, but why not add an excellent water block? The one you're using is just OK but really is outclassed by the rest of your components IMO. I wonder what your TEC hot side is? As long as you can maintain under 50C on your hot side of the TEC it should continue to cool. 32c to 37c is a really good temp differential so it does seem like your WB is moving a lot of heat. Lets assume that's not the problem. Finally, for voltage it's pretty good practice to keep it below 80% rated TEC voltage so up to that level you're OK. With fatigue your PSU could be experiencing voltage drop. Hook up a multimeter to make sure it's not dropping out because as the TEC gets hotter it will draw more amperage. This could explain the heat rise.