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FAQ Gathering
- Thread starter Thelemac
- Start date
It would be awesome if you could test a water cooling rig with different pumps and make a chart showing how cooling performance changes with the power of the pump. If you got real clever you might even be able to make a formula!!! And, maybe the same for radiators.
A chart comparing copper water blocks to aluminum or other materials. Both theoretical and tested values.
A chart comparing copper water blocks to aluminum or other materials. Both theoretical and tested values.
- Joined
- Dec 22, 2000
As far as watercooling goes...
What cooling mediums have been used? What are the pros/cons of each?
Talk about problems of using liquid nitrogen, liquid helium..
Talk about shims- Good/Bad?
I'll think of more...
***Oh Yea i'd |3u|v|[]D her***
What cooling mediums have been used? What are the pros/cons of each?
Talk about problems of using liquid nitrogen, liquid helium..
Talk about shims- Good/Bad?
I'll think of more...
***Oh Yea i'd |3u|v|[]D her***
- Joined
- Jun 9, 2001
how about some math?? like in depth definitions of C/W, thermal coefficients, thermal capacity, thermal conductivity charts, simple electronics [like calculating ohms required to drop a fan's voltage to 7v] or replacing that boring green case "on" LED with a blue one, how to calculate watts dissapated at OCed speeds, a more advanced relay mod for water coolers [one which allows manual on + auto on, easily done], overclocking debugging [to find exact source of instability to correct it], the list goes on and on
something that's pretty rare is info on sound... such as sound energy doubles every 3dB and human perception of sound [loudness] doubles every 10dB. dBA means an A-weighted scale. Or addition of dB is a logarithmic function [as in 30dB + 40dB != 70dB] it is acually only 40.414dB. Or how about the decrease of sound by 6dB for each doubling in distance. Sound deadening material types [what frequencies each is good for.] Methods of noise control vs performance, etc. I have made formulas for most of the above if you would like for me to post them.
something that's pretty rare is info on sound... such as sound energy doubles every 3dB and human perception of sound [loudness] doubles every 10dB. dBA means an A-weighted scale. Or addition of dB is a logarithmic function [as in 30dB + 40dB != 70dB] it is acually only 40.414dB. Or how about the decrease of sound by 6dB for each doubling in distance. Sound deadening material types [what frequencies each is good for.] Methods of noise control vs performance, etc. I have made formulas for most of the above if you would like for me to post them.
W
William
Guest
oooh, the sound thing, we had a very very good thread about this not too long ago, i had to pull out the physics book lol! BUMP
Looks like the Cooling team has their hands full.
Looks like the Cooling team has their hands full.
OP
- Joined
- Mar 15, 2001
- Thread Starter
- #27
You know what? Those are great ideas. If you happen to know the answers to such things, feel free to email them to me. Include whatever iformation you would like to be creditied with. You could post them, if you like, but to keep this thread a bit cleaner, I would prefer email.
Thanks for the other input guys. Keep it coming!
BUMP!
- Joined
- Jun 9, 2001
I have tried to email you [the creator of this thread] but I get an error :-( So I am posting it [I hope this board doesn't have message limits on] Here goes...
yup the limit is 4098 characters... admins: why 4098?? why not 4096? it doesn't fit the pattern 2^(n+1) like everything computery
yup the limit is 4098 characters... admins: why 4098?? why not 4096? it doesn't fit the pattern 2^(n+1) like everything computery
- Joined
- Jun 9, 2001
First part:
Here's the stuff you asked for. Give credit to me [David Priebel or Sharp.] I verified the information below with sources all over the net. You'll have to edit the wording of it a little [I used the word "I" in a few parts so you'll have to put my name there, stuff like that.] You will probably want to expand on it too. It is just a barebones start. Hope there's no really bad errors
definition of C/W [look on this page]
Thermal conductivity - This describes how well [or bad] a substance transfers heat. It is usually expressed in units of W/m·K. The energy transfer rate through a body is proportional to the temperature gradient across the body and its cross sectional area. The larger the thermal conductivity value the better conductor of heat.
Silver 420,000
Gold 310,000
Copper 300,000
Aluminum 150,000
Brass 150,000
Platinum 69,000
Iron, cas 65,000
Zinc 64,000
Iron, wrought 58,000
Nickel 58,000
Steel, soft 46,000
Lead 35,000
Mercury 7,000
Water 0.6
Air 0.026
Thermal capacity - This is essentially how much heat a transfer medium can hold. You'll have to find the charts for this one, didn't find any [with a quick search]
Resistor calculations - This calculation will allow you to figure out the resistor value required to drop the voltage and current of a power source to a specific level. Here it is:
Rs = (Vin - Vout)/Iout
Rs is resistance
Vin is voltage in
Vout is the voltage output
Iout is the current output
for instance if you have a 5v power source and a blue LED which requires 3.7v 20ma the resistance would be:
65 = (5 - 3.7)/0.02
Use the next closest higher resistor value to whatever is returned.
Green case LED to blue mod - This is a simple mod to change your boring green case LED to a blue one. I'll assume some basic electronics knowledge here. To do it I used a 3.7v 20ma 2,600mcd blue LED from Radio Shack, part #276-316. I used a 985 ohm resistor I had laying around and it seems to provide a good brightness, but I reccomend you use a higher value. I decided to do this mod a while back but found out that all blue LEDs use higher voltages than the standard 1.7 volts for most LEDs. I thought I would have to run the LED off of the 5v or 12v lines which would be messy and time consuming [didn't want to do it.] For some reason I had my computer on one day and decided to test the voltage being supplied to the LED by the motherboard... I got a pleasant surprise.. It uses 5v! That's a pretty odd voltage for an LED but hey I've seen stranger. The LED is 5mm where the normal case LED size is 3mm so you will have to drill the hole larger using a hand saw [be careful.] Wire the resistor inline and in series with the LED and make sure [!] you get the polarity correct [easiest way is to look for the indentation on the side of the current green LED and connect the same color wire to the indented side of the blue LED.] Remember to shrink wrap or otherwise insulate the connections and solder them [don't be cheap and just twist it together.] Using the 985 ohm resistor it is still quite bright so you may wish to use a higher value. I meant to [but forgot] to use a 5k potentiometer along with the 985 ohm resistor to be able to fine tune the brightness.
Here's the stuff you asked for. Give credit to me [David Priebel or Sharp.] I verified the information below with sources all over the net. You'll have to edit the wording of it a little [I used the word "I" in a few parts so you'll have to put my name there, stuff like that.] You will probably want to expand on it too. It is just a barebones start. Hope there's no really bad errors
definition of C/W [look on this page]
Thermal conductivity - This describes how well [or bad] a substance transfers heat. It is usually expressed in units of W/m·K. The energy transfer rate through a body is proportional to the temperature gradient across the body and its cross sectional area. The larger the thermal conductivity value the better conductor of heat.
Silver 420,000
Gold 310,000
Copper 300,000
Aluminum 150,000
Brass 150,000
Platinum 69,000
Iron, cas 65,000
Zinc 64,000
Iron, wrought 58,000
Nickel 58,000
Steel, soft 46,000
Lead 35,000
Mercury 7,000
Water 0.6
Air 0.026
Thermal capacity - This is essentially how much heat a transfer medium can hold. You'll have to find the charts for this one, didn't find any [with a quick search]
Resistor calculations - This calculation will allow you to figure out the resistor value required to drop the voltage and current of a power source to a specific level. Here it is:
Rs = (Vin - Vout)/Iout
Rs is resistance
Vin is voltage in
Vout is the voltage output
Iout is the current output
for instance if you have a 5v power source and a blue LED which requires 3.7v 20ma the resistance would be:
65 = (5 - 3.7)/0.02
Use the next closest higher resistor value to whatever is returned.
Green case LED to blue mod - This is a simple mod to change your boring green case LED to a blue one. I'll assume some basic electronics knowledge here. To do it I used a 3.7v 20ma 2,600mcd blue LED from Radio Shack, part #276-316. I used a 985 ohm resistor I had laying around and it seems to provide a good brightness, but I reccomend you use a higher value. I decided to do this mod a while back but found out that all blue LEDs use higher voltages than the standard 1.7 volts for most LEDs. I thought I would have to run the LED off of the 5v or 12v lines which would be messy and time consuming [didn't want to do it.] For some reason I had my computer on one day and decided to test the voltage being supplied to the LED by the motherboard... I got a pleasant surprise.. It uses 5v! That's a pretty odd voltage for an LED but hey I've seen stranger. The LED is 5mm where the normal case LED size is 3mm so you will have to drill the hole larger using a hand saw [be careful.] Wire the resistor inline and in series with the LED and make sure [!] you get the polarity correct [easiest way is to look for the indentation on the side of the current green LED and connect the same color wire to the indented side of the blue LED.] Remember to shrink wrap or otherwise insulate the connections and solder them [don't be cheap and just twist it together
.] Using the 985 ohm resistor it is still quite bright so you may wish to use a higher value. I meant to [but forgot] to use a 5k potentiometer along with the 985 ohm resistor to be able to fine tune the brightness.
- Joined
- Jun 9, 2001
2nd part:
Watt calculations - Watts dissapated by your processor can be approximated using this formula:
Watts overclocked = Watts regular(overclock speed/regular speed)(overclock volts/regular volts)^2
As you can see watts dissapated is directly proportional to speed difference and exponentially proportional to voltage increase.
Better relay mod - This mod is the same as most other relay mods to automatically start the pump along with the computer. The main difference is that a switch is wired in parallel with the relay. Basically find a switch rated high enough to power the pump and then connect it to the relay's NC and Com connectors. You may now power the pump on and off even when the computer is off, but you can't power it off when the computer is on.
overclocking debugging - too much to write, you can compile this one
dB(A) - dB(A) stands for decibel(A-weighted) and is a scale to quantify sound measurement relative to human perception. The A-weighted scale takes into account the human ear's perception of sounds at different frequencies and adjusts the dB scale to that. Humans hear better at medium frequencies than at low or high freqencies. B and C scales also exist.
Sound energy - Sound energy describes the amount of pressure a sound exerts. It is usually expressed as dB. Sound energy doubles every 3dB. Do not confuse sound energy with the human perception of sound. I have come up with a simple calculation that'll give you an idea how many times more energy one sound source has versus another:
EL = 2^((dB1 - dB2)/3)
dB1 is the higher dB level
dB2 is the lower dB level
EL is a proprietary unit I came up with to figure out how many times more energy one sound has versus another [I found no other calculation to easily compare energy levels thus I came up with this]
Sound perception - Sound perception describes how "loud" a sound is to the human ear. It is expressed as dBA. Sound perception doubles every 10dB even though sound energy doubles every 3dB. I have come up with this simple calculation that'll give you an idea how many times louder one sound seems than another:
LP = 2^((dB1 - dB2)/10)
dB1 is the higher dB level
dB2 is the lower dB level
LP is a proprietary unit I came up with to figure out how many times louder one sound seems versus another [again I came up with this because I couldn't find any other similar calculation, one may exist]
Sound addition - Sound is measured using dB and dB are on a logarithmic scale. That means you can't simply add two sound source's dBs together. For instance if you have one source that emits 35dB and another 40dB the output level is NOT 75dB. It is actually 41.19dB. To add two or more sound sources use this:
10*log (10^(dB1/10) + 10^(dB2/10) + and so on)
To add 35dB to 40dB you would do this:
10*log (10^(35/10) + 10^(40/10)) = 41.19dB
Sound Decay - Sound levels decrease at a rate of 6dB per doubling of distance. This is obviously affected by surfaces reflecting the sound but it's a good approximation. Spefically it describes a point source outside. Here is a calculation I have come up with that'll approximate sound decay:
dB = dB in - 6(log D/log 2)
dB is the output dB
dB in is the input dB
D is the distance from the source
Sound deadening - too much to write again, you do this one. Make sure to differentiate between vibration dampening, sound dampening, active sound cancellation, etc. Also, mention different materials are better for different frequencies [they are designed for them.]
- David Priebel aka Sharp
Watt calculations - Watts dissapated by your processor can be approximated using this formula:
Watts overclocked = Watts regular(overclock speed/regular speed)(overclock volts/regular volts)^2
As you can see watts dissapated is directly proportional to speed difference and exponentially proportional to voltage increase.
Better relay mod - This mod is the same as most other relay mods to automatically start the pump along with the computer. The main difference is that a switch is wired in parallel with the relay. Basically find a switch rated high enough to power the pump and then connect it to the relay's NC and Com connectors. You may now power the pump on and off even when the computer is off, but you can't power it off when the computer is on.
overclocking debugging - too much to write, you can compile this one
dB(A) - dB(A) stands for decibel(A-weighted) and is a scale to quantify sound measurement relative to human perception. The A-weighted scale takes into account the human ear's perception of sounds at different frequencies and adjusts the dB scale to that. Humans hear better at medium frequencies than at low or high freqencies. B and C scales also exist.
Sound energy - Sound energy describes the amount of pressure a sound exerts. It is usually expressed as dB. Sound energy doubles every 3dB. Do not confuse sound energy with the human perception of sound. I have come up with a simple calculation that'll give you an idea how many times more energy one sound source has versus another:
EL = 2^((dB1 - dB2)/3)
dB1 is the higher dB level
dB2 is the lower dB level
EL is a proprietary unit I came up with to figure out how many times more energy one sound has versus another [I found no other calculation to easily compare energy levels thus I came up with this]
Sound perception - Sound perception describes how "loud" a sound is to the human ear. It is expressed as dBA. Sound perception doubles every 10dB even though sound energy doubles every 3dB. I have come up with this simple calculation that'll give you an idea how many times louder one sound seems than another:
LP = 2^((dB1 - dB2)/10)
dB1 is the higher dB level
dB2 is the lower dB level
LP is a proprietary unit I came up with to figure out how many times louder one sound seems versus another [again I came up with this because I couldn't find any other similar calculation, one may exist]
Sound addition - Sound is measured using dB and dB are on a logarithmic scale. That means you can't simply add two sound source's dBs together. For instance if you have one source that emits 35dB and another 40dB the output level is NOT 75dB. It is actually 41.19dB. To add two or more sound sources use this:
10*log (10^(dB1/10) + 10^(dB2/10) + and so on)
To add 35dB to 40dB you would do this:
10*log (10^(35/10) + 10^(40/10)) = 41.19dB
Sound Decay - Sound levels decrease at a rate of 6dB per doubling of distance. This is obviously affected by surfaces reflecting the sound but it's a good approximation. Spefically it describes a point source outside. Here is a calculation I have come up with that'll approximate sound decay:
dB = dB in - 6(log D/log 2)
dB is the output dB
dB in is the input dB
D is the distance from the source
Sound deadening - too much to write again, you do this one. Make sure to differentiate between vibration dampening, sound dampening, active sound cancellation, etc. Also, mention different materials are better for different frequencies [they are designed for them.]
- David Priebel aka Sharp
