FAQ Gathering

[Thelemac]

Please assist us in the effort to put together the most comprehensive FAQ for overclocking. All assistance is appreciated.

I would ask you to post any questions that you have had about cooling here. Answers that you have recieved would be great, too.

Please bump! :)

[wildone]

Bump!!!!!

[sfa ok]

Some questions that I've heard a few times are:
"Is this too hot?"
"How much thermal compound?"
"Safety of water cooling?"
"Wattage of TEC?"
"Power for TEC?"
and general noise issues

[UnseenMenace]

I wouldnt mind a FAQ on mounting alternitive fans on heatsinks.
I use a FOP-32 with a Y-Tech fan and dont really want the noise of a delta.. so how about telling me what options are availble.. such as a 80mm fan or funnel with fan on case

[William]

This is one of the things I would like to see here. A mini snipet on a bunch of the hsfs out there now. Like what each would be good to run with etc. It is a lot of work but that is probably the most asked question out there.

[Blue Jester_2112]

Some more frequent questions might be:
"What is lapping?"
""What grit sandpaper?"
"Wet or dry sanding?"
"Do I apply the thermal paste to the HS or the cpu die?"

Perhaps a warning about Orbs would be good.
If your going for a really indepth FAQ then a table showing what temps are normal for different cpu types might be very informative since the questions of "Are these temps normal?" and "Is this too hot?" come up alot. Maybe just a chart showing the potential danger zone for different cpu's.

[el]

Blue Jester_2112 (Jul 02, 2001 09:04 a.m.):
Some more frequent questions might be:
"What is lapping?"
""What grit sandpaper?"
"Wet or dry sanding?"
"Do I apply the thermal paste to the HS or the cpu die?"

Perhaps a warning about Orbs would be good.
If your going for a really indepth FAQ then a table showing what temps are normal for different cpu types might be very informative since the questions of "Are these temps normal?" and "Is this too hot?" come up alot. Maybe just a chart showing the potential danger zone for different cpu's.


Step by Step Lapping would be great with links and ideas where to find the small grit sandpaper.--Auto body shops have it.

[cjtune]

You'd probably need some basic info on the function of fans and pumps. eg. the characteristics of centrifugal/crossflow blowers vs. axial fans, typical fan (and pump) performance data sheet (pressure vs. flow chart), fan voltage and switching mods, inline vs. submersible pumps, and maybe some cost analysis to compare between the expenditure and gain of HSF, water, and TEC setups (give ppl some idea on how much to spend to they don't make themselves poor overclocking!). Speaking of TECs... maybe some equations to size a peltier according to need (eg. what is the wattage of a peltier I need so as to not overspend...or accidentally cook my bird). Yeah, don't forget a checklist of all the hardware (dremel, nibbler, sandpaper, etc.) your 'average' overclocker might need for each type of cooling project :)

[cjtune]

Oh yeah... BUMP!!!! (Ow, my head! Gotta..wipe...away...blood...on table...before.........passing.................... ....out........*)

[AMDGuy]

More in depth questions I've been asked:

1. How to wire up Relay to power water pump?
answer here: http://www.overclockers.com/tips242/

2. Why won't my computer boot after doing VMOD.
answer: You hit the over voltage protection of the IC you need to also do the stage 2 mod if you wish to go over 2.1V.

3. What is battery effect (aka galvanic corrosion)when referring to Copper and Aluminum metals and watercooling.
answer: Dissimilar metals cause a reaction with each other in which corosion occurs in these parts. You'll need to use Water Wetter or a smilar product if you chose to mix Aluminum and Copper parts in a watercooing setup. Recommendation is to use all copper.

and

BUMP!

[JaY_III]

pmub | bump

[Shadow ÒÓ]

bbbhhhuuummmppp

[Paul -The Mad Hatter]

bubump

[William]

What is a peltier?
Do I need a pelt?
Whats the best Watercooling rig?
Whats a bong tower?
What do I add to the water?
Why is water the best to use in cooling?
What fan do i use.............

[Bad Maniac]

-Alternative methids of mounting fans. like using silicone to prevent vibrations. making ducts for airflow.

-How and WHERE to place extra fans to increase airflow.

-once and for all! what are the different heattransfer values of different materials. Gold, Aluminum, Silver, Unobtainium, and Diamond.

-What resonable mobo/cpu temps are for different setups.

*kabump*

[Bad Maniac]

Oh yeah!
- How to build your own water cooling rig. What materials to use, and where to obtain them.

[Thelemac]

Thanks for all the great feed back, guys! Keep it coming!

*bump*

[whiskeyinajar]

cleaning radiators?
power supply for pelts?
getting air out of water cooling system?
sealing leaks on anything?
condensation prevention?
diff types of pumps?
Wiring rehostats/resistors/2powersupplies/and pumps

[sieb]

How bout a list of procs and speeds and what the best cooling solution is for each HSF wise or other so I dont have to buy and test all the them myself. :)

[Thelemac]

More great ideas, thanks guys!

Sorry about the delay in responding, but I've been out of range of a non-long distance number from a hotel for a week or so now.

BUMP!!

[JaY_III]

bump

[Ferg]

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.

[CreePinG_DeatH_reverted]

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***

[cjtune]

Don't forget sound-proofing!

Bumpety-BUMP!!

[Sharp]

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.

[William]

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.

[Thelemac]

Sharp (Jul 10, 2001 01:41 a.m.):
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.

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!

[Thelemac]

bump

:D :D :D :D :D :D :D :D :D :D :D :D :D :D

[Sharp]

ok, I'll compile a list of the things I've mentioned to add to your FAQ [may take a little time]

*bump*

[Sharp]

Well, I'm done and I was going to post it but it is 3 pages long :-(. I'll email it to you and anyone else that wants it. If a lot of people want it I'll post it.

[Amedeo602]

I'd like to see it

*bump*

[Sharp]

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 :-)

[Sharp]

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.

[Sharp]

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

[Eil Atan]

a section on optimal placement of fand for keeping ambient temperatue low (among other things) for both crammed cases (like mine) and full towers with lots of space... the FAQ sounds like its gonna be great...

[Thelemac]

bump

[Thelemac]

bump

[Sharp]

* bump, bump bump * [Kottonmouth Kings :-)]