Case dilemma!

[Sniper]

Ok So with i7 getting so hot it needs more than a double rad to cool it imo.

Here's my dilemma should I stick with my H2g0 & finish my build anyways OR put my build off even longer & sell the h2g0 to get the pinnacle24 with a triple rad setup? It'll cost about $500 for the new case -whatever I sell the H2g0 for of course.

[Fitseries3]

MM = overpriced/overated IMHO

[Sniper]

that's it Fits i'm getting skin grafts! lol

http://i11.photobucket.com/albums/a170/2low4u/cutting.jpg

[Septim]

build your own FTW!

[Sniper]

well I wish I had the means to dude or I prolly could. I can build just about anything I put my mind to if givin the somewhat proper tools lol.

So I decided to stick with the H2g0 for the time being & to beat the heat i'm going with a TEC which is something I've wanted to do for awhile now.

[Fitseries3]

i have all the big nice tools but its more of a challenge to build everything by had like i do. i bet you never knew i built everything by hand :)

[Overclocking101]

good luck finding a TEC that will cool an I7. The TEC's nowadays have a hard time with a core 2 quad let alone the heat of i7.

[Cutless009]

good luck finding a TEC that will cool an I7. The TEC's nowadays have a hard time with a core 2 quad let alone the heat of i7.

I thought the point of TEC water blocks were that they cool better than just a water block D: I cant imagine how they wouldnt o.o

[Langer]

Please correct me if Im wrong.

The CPU is a 125WATT unit - I'm assuming that it's maximum draw is then 125W. Regardless of this stat, my theory lesson still applies.

Since the cpu is drawing 125W it is then limited to the creation 125W of heat.
Considering that you could easily find a 600W+ TEC (peltier, if you'd prefer) I can't foresee how cooling a 125W i7 can be a challenge.
Especially considering that many thousands of people around the world have achieved double digit negative temps using pelt systems over the years.

[Sniper]

Your correct from what I gather Langer. Here's Fits temps when he had his setup on his i920.

http://forums.techpowerup.com/showpost.php?p=1065269&postcount=27

[Baleful]

Aren't you missing something though? If the rad you are using now isn't enough to properly cool the i7, adding a TEC to the loop is only going to saturate the rad even more right?

I'm not sure if what Langer said is true, but lets say it is.

i7 = 125 Watts
TEC you would need = ~250 Watts

This means the TEC is gonna dump twice the amount of heat into your loop compared to just the i7, correct?

I'm not really on the up and up on TEC's, but this just does not make sense to me. You are saying the PA 120.2 does not have enough capacity to cool the i7 therefore you are going to add a TEC into the mix, but the TEC is only going to dump more heat into the loop (overloading your already overloaded rad)

Any of this make sense to you? I'm not sure if any of this came out right lol.

[Langer]

Check this:
www.melcor.com/pdf/Thermoelectric%20Handbook.pdf
More details from dell on H2C cooling:
http://www.dell.com/downloads/global/vectors/h2c.pdf


TEC and peltier effect
What is a TEC?
A Thermo-electric-cooler (TEC, picture above) is a small solide device that can operate as heatpump or electrical generator. When used as heat pump (which is the one we want to know about), then, its called TEC thermo-electric-cooler.
If used as electrical power generator, then, its called TEG thermo-electric-generator.

When its used as TEC, it uses the peltier effect to move heat.


What does peltier effect does? How does it works?

The Peltier effect was discovered in 1834. When current passes through the junction of two different types of conductors it results in a temperature change. However, the practical application of this concept required the development of semiconductors that are good conductors of electricity but poor conductors of heat - the perfect balance for TEC performance. Today, bismuth telluride is primarily used as the semiconductor material, heavily doped to create either an excess (n-type) or a deficiency (p-type) of electrons.


Then, How does a TEC work?

The procees is very simple and easily to understand.

A TEC consists of a number of p- and n-type pairs (couples) as I mentioned above, connected electrically in series and sandwiched between two ceramic plates.

When connected to a DC power source, current causes heat to move from one side of the TEC to the other.
This process creates a hot side and a cold side on the TEC.
A typical application exposes the cold side of the TEC to the object or substance to be cooled and the hot side to a heatsink which dissapates the heat to the environment. A heat exchanger (e.g. Good heatsink or Watercooling system) may be required.


Lets return to our little adventure.

First of all, we need to check the Thermaltakes peltier system, which seems to be ready to work without problems.

We can see its peltier, its heatsink fan, and a PCI slot card which controls the wattage on the peltier.

At first, we see the peltier and we probably would think about buying something like that, since it seems that cools better than Watercooling and the proce is around 120 dollars.

But, wait a minute. At first, we can see that Thermaltakes bundles a very small and it seems that it wont perform as well as a Big Typhoon or a Thermalright heatsink.

Then, I think, why does it comes with such a small heatsink if the peltier needs a good cooling system or any other could cause the peltier to get hotter making a disaster in your PC??

So, the maximum wattage in this TT´s product is 73w.
Although it seems a lot of energy (similar to a non-overclocked processor) lets continue with the scientific explanation.


Rules to consider when using a TEC

When using a TEC, there are some things we need to consider before installing it.

First of all.
The wattage in the TEC is very important, since its going to define, how cooler and hot hotter the peltier would be.

There is an easy rule when doing this.
The rule, known as Delta-T needs some easy factors

-the CPU wattage compsumption
-Peltier wattage compsumption
-Max teorical temp (more info can be found in Intel and AMD supports/ processor/specs official pages)

The formula would be like this.
(1-(CPU wattage compsumption/peltier wattage)) x Max teorical temp

Then, lets take an example

My PC uses an AMD opteron 146 which works at 1.4v from stock.
Its wattage compsumption is 76 watts.
Then, the Thermaltalke´s peltier uses a max of 73 watts

AMD specified max teorical temp is something about 70ºc, but since we really F.E.A.R. to use it above 55ºC then where using as the max teorical temp.

Pentium 4 has a limit of 67ºC or sometimes 69ºC.


So, we have.
(1-(76/73))x55
(1-(1.041))x55
(-.041)x55
-2.55

As we can see, the result is negative. What does this means?

Reading some articles and reviews and users posts we can see that these product is rejected from users.
Users usually post that they considered it to work better or they even said it works worst than its older heatsink-fan.

Lets imagine that my Opteron worked at 35ºC idle and 50ºC at full load.
Using this cooler would increase my temps by 2.5ºC degrees, so thats why negative results are important.
If the result from the formula would have been possitive, lets imagine +2.5. Then, i would have gained 2.5ºC from my CPU (which really is not that much).

So, thats why users report bad results and commentaries from this product.


But, wait a minute......


Lets continue the adventure

Since I was dissapointed from this product, i started to check other peltiers from other brands.

I found in www.frozencpu.com some peltiers which seemes to be very inexpensive.

http://www.frozencpu.com/scan/se=Wat...nu_search.html

The first one, using 80 watts which seemed a little bit higher than the TT´s one.
The second one, using 226 watts which is almost 3 times bigger than the first one.
And the third one, using 437 watts (almost double the 226 watts)

So, doing some research i found that 226 watts for a peltier was the most recommended.

Before users install a peltier with that amount of wattage, they need to get a very good PSU.
Since its not the same adding 80 watts (similar to a 6800 ultra) vs adding a 226 watts peltier (which is like having a PC in idle) or a 437 watts peltier ( as much as a powerfull PC in load).

So, there are two possibilities.

The first one is buying a very good PSU with a good amperage and at least 500 watts, and the second would be buying a second PSU with just 300 watts and a good amperage just for the peltier.

I really recomend the second since the peltier will have its own PSU and if anything goes bad, it wont affect all other components connected to the PSU.

So, having a 226 watts peltier will result into this.

(1-(67/226))x55
(1-(.296)x55
(.704)x55
38.72

That menas than using a peltier with such wattage and a CPU with such a low wattage would result into a possitive 38ºC degrees reduction!!!!

Lets imagine my CPU is running at 40 idle and 55ºC in load.
So, with a powerfull 226w peltier, i could have almost subzero temps at idle and less than 20ºC in load. Fantastic right??

So, thats why OCers could use this as a very good option.
But, what happens when we overclock?

Using my CPU at 3200ghz and 1.6v would increase my 67 watts to 140 watts.

I know its a big increase, but its real.

then

(1-(140/226))x55
(1-(.619)x55
(.381)x55
20.9

Which goes into a 20ºC degrees reduction in temps which are far better than a water cooling system.


You're actually correct Baleful.

Assuming that the i7 draws a max of 125watts, and likely actually uses lower, you could probally get away with a ~100watt pelt and still have overhead for clocking.

If you were looking for sub-z temps then YES you will need a larger pelt (400watts for example) that will wick more heat away from your CPU, but it'll also create an additional 400watts of heat that will need dissipating.

[Sniper]

I'll be using a 226W pelt for this project. I don't think it will heat up as bad as what some may think. I'll try it & if it isn't what I expect in this setup I'll save it for the next. Not a big problem really.

[Baleful]

Hmm.... I'm confused, you are saying the radiator you have now isn't enough to cool the i7 (which means it's saturated). Having a pelt on the CPU is only going to add even more heat into the loop.... doubled what the i7 is putting out (roughly).

I would think for this to be most effective, you would need a 120.4 or something bigger than a 120.2, i'm not sure though as I have no experience with TEC's.

[Sniper]

I'm just going by what I "heard" I haven't set my system up yet but plan to go with the tec first off anyways to see what the temps are ect. Least that's the plan for the time being. I might just say friggit & wait on it till I get a bigger setup yet I dunno. See what happens.

[Baleful]

Shit, stick it on there and try man. You never know till you try.

[Sniper]

Well that's what I was thinking to right lol. I gotta get somethin rollin on this beast soon before it's Ancient haha.

[Langer]

Baleful is correct. Adding a 225watt pelt to your system will add 225w of heat to your loop (realistically lower of course, there is no 100% efficient method of creating heat).

I misinterpreted the issue when I offered my first explination.

if you are using a 120.2 rad and an i7 - I'm pulling these numbers form my colon, sub in the correct figures at your own leisure.
lets assume that the rad has a dissipation capacity of about 150watts of heat
lets assume that the i7 produces 125W of heat.
Not lets pretend we are adding a 225w pelt to the mix.
You'll now need a rad capable of dissipating 350watts of heat.

The peltier effect is like a wick dipped in oil (where the oil represents heat, and the wick is the pelt).
oil will soak into the wick increasing it's mass.
In this example mass is like watts of heat.
lets pretend the wick was 10grams and the oil that soaked into the wick was 2grams - we've increased the mass by 2grams.
back in wattage terms:
your pelt has a wattage value, as does your i7. The pelt doesn't cancel out that energy... it just relocates it to the hot side of the ceramic pad.

In simple terms: [pelt wattage + cpu wattage - radiator heatsink value]
IF you get a positive number you should be good... if it's negative you have a problem.

Even though the i7 will be cool for a little while - your liquid will reach its point of equilibrium - and it will be very hot. Eventually it wont be able to dissipate the heat you are producing and the pelt will blow (crack) and then your i7 will follow suite.

I linked you a formula above (i highlighted it red above) ... use it to determine your projected cooling results.

I'd also contact your rad manufacturer and ask them for the maximum heat dissipation value for your rad (if they don't give you a number in watts, I can convert it to watts for you).
You'll also have to remember that adding another PSU to your case - for the pelt - is in its self going to add even more watts of heat in the form of increased ambient air temperature inside the chassis.

[Sniper]

Yeah I understand Langer. In this case it would be mounted on the outside if anywhere but it won't be feasable to use it in such a confined space with the size rads I have atm. If my case sells & I step up to bigger rads then I'll do this for sure. You reminded me what I went over a couple months ago but wasn't thinking about again. Thx dude haha. Now I remember why I didn't buy that Swiftech pelt when it was on for half price from NCIX lol.

[Langer]

in your case:
1 - ((132 / 225) * 73) = -41.8266667

You can expect a drop in temps by upwards and more than 41degrees... assuming you have a "heatsink" capable of 357WATTS of dissipation

There's huge gains to be had. But I dont know the thermal dissipation value of your Rad.

[Sniper]

yeah I'll be either using a Bix or PA double 120. Both will be in the case but one has to be dedicated to the 3 vids to though.

[Langer]

You may even see an issue running all 3xGPUs on 1x240mm RAD.
GTX280's can develop near 160watts of HEAT each.

A couple years ago, even 12months ago, that 240mm RAD would have been sufficient - but the times they are a changin'... what was law is no longer directly applicable with modern hardware. Our systems are drawing a hell of a lot of power these days, and with that comes more heat than ever before.

I'm even weary of having my Phenom in the same loop as 2xGTX280's with a 360mm rad.


IMO and from what I've seen despite the relatively low initial power draw; i7 chips need a dedicated 360mm rad for reasonable overclocking potential.
The power draws of these chips balloons when you start overclocking.

As an example from the article above: "Using my CPU at 3200ghz and 1.6v would increase my 67 watts to 140 watts."
The new i7 chips are even worse for this power spike than the old s939 Athlons.

[Sniper]

Yeah I know uhg! I'm running 3 8800GTXs currently(or plan to) with one 240 rad dedicated to them then a 120 will be for the chipsets. UNLESS i sell my case then I'll have more space & will be going with a PA120.3 for sure! with the rest as well so that'll be deff sufficient for what I had in mind. I might just say hell with it & buy the new case anyways without waiting for mine to sell. See what kinda coin I can come up with here in the next little bit. If I do this then I will be able to keep my current PSU to so that will be a bonus for me as well.

[Langer]

I think you may have to step up.

But I'd try what you have first - that wont cost you anything and it may be sufficient.

(did you get a Liquid Evolution res?)

[Sniper]

Yeah I have that res in the pic there. Haven't tried it yet so dunno how it's going to work out. I was told it was never used so they didn't know if it leaked or not.