Moving to Denver, question about cooling

[Russwinters]

Alright, so I am moving to Denver soon and I am just wondering if anyone has experienced what kind of effect being at 5000ft has on the cooling system of your PC

All my temps are well below any critical levels already, and I am pretty confident it will still stay well under, but I am a bit OCD about temps, and like to keep my PC nice a cool.

Can anyone share their experience with cooling in higher altitudes ~5000ft? Does this put more stress on your fans, potentially killing them faster?

using a Q6600 (yeah, about due for a new system anyways haha) @ 3.0GHZ and no extra voltage needed. Using a thermalright 128-SI with Scythe Ultra Kaze 3K, temps@load never exceed ~44c, even in the summer. That is in California (sea level)

I am more worried about my fans dying then my temps spiking alot, I expect that my temps will only rise by a few c, but I am wondering if the thinner atmosphere may cause the fan motors to burn out.

I heard some things here and there that certain types of fan bearings/motor/blades are designed better for higher altitudes, can anyone clarify?

Thanks!

 

[Zap]

The only thing I can think of is to use fans that have higher static pressure, like the ones popular for use on radiators. The reason would be because air pressure is lower. Other than that, I don't think altitude will have any effect on your system temperatures.

 

[Wuzup101]

Take a look at this for some interesting reading: http://www.comairrotron.com/engineering_notes_02.asp

In either case (please don't take offence to the following... as none is intended): This is one of those problems that is interesting theoretically but has little to no practical meaning for you. People in Denver have computers... they work. There may be a drop in heat transfer at a given flow rate but it should really be insignificant. You are not going to see a 30C jump... you probably won't see a 3C jump... and even if you do see a 3C jump... it won't mean anything because you'll still be WELL under the safe temps for your processor. You probably won't experience more than a 15% drop in air density by going from 0 to 5k feet... that would be a straight reduction in mass flow by the same amount... not likely to account for more than a few degrees C.

Also: I have absolutely no clue how it will actually effect your fans... but again I will apply the "people in Denver have computers" concept (sorry I had to). My first thought would be that the decreased air density would reduce wear on the fan due to less resistance per volume of air pushed through the fan (or less wear per operating time). Not a clue if that's correct though.

Seriously though... it IS an interesting question... I would love to see some actual data once you move!

 

[GoSharks]

You are over analyzing. Nothing will happen.

 

[stahlhart]

You are over analyzing. Nothing will happen.

Yup.

(has family in Co. Springs)

 

[billyb0b]

i live in colorado, the gps on my phone shows my computer right at 6,744 feet right now.

you're over thinking this, nothing will happen, it will cool fine

 

[pm]

Actually, it's the opposite. The air is thinner which results in the fan having to work less hard to move the air (less resistance) which results in less of a load on fans, but less cooling as well.

I build and fly electric model airplanes and I find to get the same amount of speed/thrust, I have to make the propeller larger/higher pitch. Otherwise I find it moves less air, resulting in longer flight times, but less power and speed. It's the same with case fans, they will move about 20% less air.

As far as high altitude fan designs, there almost definitely are such things. You need to increase the prop size, or increase the prop pitch (the angle of the blades) to compensate for the thinner air. I can't quite picture high altitude bearings though... most of these brushless fan motors use sleeve bearings (except the high-end ones) and you shouldn't find any difference between a low altitude sleeve bearing and a high altitude one.

see this article:
http://www.rcgroups.com/forums/showthread.php?t=213592

One of the recurring subjects on both the Eflight mailing list and the Slow Flight list, and now here on the Ezone discussion boards, comes from a newcomer to electric flight who lives in the Rocky Mountain region of the United States or someplace else well above sea level and who has been told by some so-called experts (often in a local hobby shop) that "electrics don't work at this altitude - they're too heavy". Well, I'm here to tell you that those local "experts" are wrong! Instead, electrics work BETTER at higher altitudes than their glow-powered counterparts. In fact, the world altitude record for propeller driven aircraft, 96,500 feet is held by an electric! You can read more about that airplane here:

http://www.aerovironment.com/news/news-archive/813flight.html

Not only do electrics work better than their IC powered counterparts at altitude, but all you have to do to make an electric airplane perform just about like it would at sea level is to change something that's pretty easy to change - the propeller.

(IC is Internal Combustion, and "glow" refers to the spark plugs and is another reference to IC engines).

I build my own electric motors too... I don't do anything special in my designs to compensate for altitude - just change the prop diameter/pitch.



But this has little effect in the big picture. Slightly less effective cooling, slightly lower power draw on the motor. Not a lot of effect overall. It's like the effect of cosmic radiation on computer reliability - there is an effect (your computer is slightly more unstable at 5200ft than at sea level) but it's not a large enough effect to really notice unless you are trying to run a high reliability server.


By the way, welcome to Colorado! My wife and I moved here about 15 years ago "temporarily" and we never left. We are very happy here.

 

[Russwinters]

Take a look at this for some interesting reading: http://www.comairrotron.com/engineering_notes_02.asp

In either case (please don't take offence to the following... as none is intended): This is one of those problems that is interesting theoretically but has little to no practical meaning for you. People in Denver have computers... they work. There may be a drop in heat transfer at a given flow rate but it should really be insignificant. You are not going to see a 30C jump... you probably won't see a 3C jump... and even if you do see a 3C jump... it won't mean anything because you'll still be WELL under the safe temps for your processor. You probably won't experience more than a 15% drop in air density by going from 0 to 5k feet... that would be a straight reduction in mass flow by the same amount... not likely to account for more than a few degrees C.

Also: I have absolutely no clue how it will actually effect your fans... but again I will apply the "people in Denver have computers" concept (sorry I had to). My first thought would be that the decreased air density would reduce wear on the fan due to less resistance per volume of air pushed through the fan (or less wear per operating time). Not a clue if that's correct though.

Seriously though... it IS an interesting question... I would love to see some actual data once you move!

Yeah, I had taken a look at that website previously and pretty much decided that I wouldn't see a big difference, but figured that I would ask on here knowing that there had to be people living their that could give me their real life account.

No worries about the "people in Denver have computers", haha, I am fully aware of this, but I always strive to increase my understanding in computers in all fields and areas; so while I knew that my computer wouldn't explode, I was really just curious of how much the atmospheric change would actually effect it.

I am a professional data recovery technician, so my job is to over analyze things, and I tend to bring that habit into almost every aspect of my life. I thirst for knowledge!

For instance, higher altitudes DO noticeably effect HDD as the read/write heads rely on an air bearing to allow them to float safely above the platter surface, when there is less atmosphere, the heads fly closer to the platters potentially increasing the risk of head crash.

 

[Russwinters]

Actually, it's the opposite. The air is thinner which results in the fan having to work less hard to move the air (less resistance) which results in less of a load on fans, but less cooling as well.

I build and fly electric model airplanes and I find to get the same amount of speed/thrust, I have to make the propeller larger/higher pitch. Otherwise I find it moves less air, resulting in longer flight times, but less power and speed. It's the same with case fans, they will move about 20% less air.

As far as high altitude fan designs, there almost definitely are such things. You need to increase the prop size, or increase the prop pitch (the angle of the blades) to compensate for the thinner air. I can't quite picture high altitude bearings though... most of these brushless fan motors use sleeve bearings (except the high-end ones) and you shouldn't find any difference between a low altitude sleeve bearing and a high altitude one.

see this article:
http://www.rcgroups.com/forums/showthread.php?t=213592


(IC is Internal Combustion, and "glow" refers to the spark plugs and is another reference to IC engines).

I build my own electric motors too... I don't do anything special in my designs to compensate for altitude - just change the prop diameter/pitch.



But this has little effect in the big picture. Slightly less effective cooling, slightly lower power draw on the motor. Not a lot of effect overall. It's like the effect of cosmic radiation on computer reliability - there is an effect (your computer is slightly more unstable at 5200ft than at sea level) but it's not a large enough effect to really notice unless you are trying to run a high reliability server.


By the way, welcome to Colorado! My wife and I moved here about 15 years ago "temporarily" and we never left. We are very happy here.

It sounds like my best bet to account for the less efficient heat transfer of the air is to decrease overall ambient temperature, and to direct lower temperature into the intake if possible.

Thanks for the kind words about the move, while I will greatly miss all of my family and friends here in california; right now it is the best decision for my wife and son, and I feel like it would be an awesome place to raise my son (he just turned 4 this feb).


Also, you should check these things out if you like remote control aircraft, apparently they are not legal in the US as they are banned by the FAA:http://www.youtube.com/watch?v=dTHWBSluUjU

 

[pm]

If you use temperature controlled fans, you shouldn't need to do anything... the other way to compensate for the thinner air resulting in slightly less cooling is to increase the RPM (on an electric plane you'd increase the voltage, but since the voltage is supplied by batteries, this usually isn't practical). So the temperature controlled fan should offset for the slight temp increase by increasing the RPM of the fan and everything should be the same (more or less).

And yeah, we moved Silicon Valley to N. Colorado for our children too. Better schools, better commute (1 hour in Silicon Valley is now 5 minutes - I usually ride my bicycle now), more reasonable housing, less crime.

That jet video is amazing. I made a plane that flew about 85mph. It was tiny - total weight of the whole plane with batteries, everything was ~4oz. I had the hardest time flying it. It was really easy to lose sight of. Finally, I pulled up too hard and snapped the wings. I can imagine how hard it is to fly and land a jet like that, I remember that my ex-speed plane was scary to fly... and mine went a lot slower... (link to my 4oz speedplane)