- Joined
- Sep 15, 2007
- Location
- Small town Emlenton, PA
My first hack. Formatting and bold etc needs worked out, looking for input. What's missing, what's redundant, redo of sections, whatever. Go for it.
Welcome to the much needed Watercooling Heatload Explanation.
A watercooled PC generates heat, some parts make massive amounts due the incredible calculations to give us what we crave. Realistic games, Folding for our future, and decoding DVDs for our own personal use.
I'm going to focus on two parts of your PC. The CPU and the GPU. These are the main hot parts we need to cool. I'll touch on a few other issues you need to understand as I hack my way through this.
I used to teach electronics to young folks, been water cooling for a few years, and I think I can help get the concept across to any new person looking to expand their knowledge and build a really nice rig. Understanding the big picture, answering the eternal Forum question, "What stuff do I need to cool my rig". I'll try to answer this.
Most importantly, I need to say, if it wasn't for all the testers who post scientific tests and not hack reviews this post wouldn't exist. These are people who for science and curiosity spent $100s++ of their own money and time building testing rigs, and COUNTLESS hours of their personal time to inform us, the uniformed public. I thank you Martin and Skinnee, you're an amazing part of our water cooling world.
Past the garbage, on to the important stuff.
Okay, you got an xx processor. What heat does it make under load? Heat is from the voltage and the amperage draw your CPU needs. Increasing voltage really increases your heatload as does your overclocks.
If a CPU uses 200 watts of power, about 80% to 90% will be lost as heat as the work is done in the CPU. It's deep electronic stuff, just go with it okay? You have to remove the heat.
You can express your required heatload in three ways.
1. Basic cruzin the web
2. Gaming
3. Benching for the best overclocks
Understand these three important things. All of them come into play.
1. Your budget
2. Acceptable noise levels
3. What can you fit in your case
Determining your heatload isn't a perfect science. You'll find numbers all over the place. From what you have learned from reading lots of info, Googling terms like "heatload i7 965, AMD xxx, Q6600 overclocked , etc. Reading 3-7 pages of Google, and following links within the Goggle links you should have an idea of what wattage you need to cool for your needs for your CPU and/or GPU.
CPU heatload
For example, I remember a Q6600 at 3.9 was 150 watts MAX. An i7 at 4.0 250 watts. Right now as I type my i7 965 stock is at 80 watts. My peak load is 340 watts, but for a very, very short time. So take the min/max with a grain of salt. These are max testing loads, so real world is a bit lower if you're a big gamer. I'm making a point, it's a lot of heat and you need to remove it. I use 250 watts as my stress wattage for my calculations on MY chip.
GPU Heatload
GPU's are a big issue now. Some are moving to watercooling, never done it before just because their GPU screams like a undead banshee when gaming etc. I have these neat links from another forum. From what others have said these folks did a TON of work, and is trusted. They were able to only look at JUST the GPU heatloads on many cards. No full system power, we all can do that with a wattmeter.
Bookmark it!
http://www.overclockers.com/forums/showthread.php?t=635806
Please, I ask you to attempt to understand your heatload before we move on.
How basic WC works in relation to heatload
We generate xx heat, the heat is transferred to the water. The cooler the water the more heat is transferred. As the water heats up its removed by the radiator. The more efficient the fan/radiator combination is, the cooler the water. The cooler the water, the cooler your parts. So simple.
Basic watercooling uses a pump, res, a block, a radiator, AND ambient air temps. Our water can be no cooler than the air temps. A room at 12C will keep the chips much cooler than a room at 30C. Remember that statement. Summers are much hotter and many back off on their overclocks in the summer. Funny thought, I just realized more people mention chilled water, mini fridges etc in the summer.
Finally to Delta T (DT) temps and why it's so important to understand them.
DT temps is the foundation of your WC loop. The better they are, the cooler your chips are. In water-cooling it's simply the difference between the ambient air temps and the water temp on the outgoing side of the rad. Room temps vs. water temps. That's it. You can't remove all the heat or can you go below ambient room temps.
When you boot up a powered off WC PC, the water temps AND your CPU are at room temp. You boot the PC up, the chip gets hot FAST. The water moves over the chip, it begins to remove heat, it goes to the radiator, SOME of the heat is removed. Not all can be removed, you have to know thermodynamics deeply (more than me) to know exactly why. The water begins to warm up slowly, and in time, the water reaches a balance, an equilibrium is reached. Heat is made and heat removed, the loop is stabilized. You change the room temp, the load, or your fan speed it needs to readjust. You increase your cooling system, the water WILL get cooler, better chip temps.
Water temps in a stabilized loop, amazingly is very little different anywhere in the loop. 2-3C difference between the radiator out temp and the CPU out temp changes little. Remember the water can't remove all the heat, just some, and some is transferred to the air. Your radiator size, effiency and fans play a big part in this. It's a system built on many parts and within the laws of physics, look at it that way. Every part effects the other.
Now that DT and loop stability is explained, let's talk about good DT temps.
A CPU loop needs good DT. Under 10C is just fine, getting closer to 5C is very nice and important if you want big overclocks. Getting under 5C is just overdoing it, unless your very xtreeme, need it for benching or just want to do it. On an average CPU loop, shoot for under 10C and adjust your overclocks to be fine, under the temps suggested by the makers.
A GPU Loop used to be fine with a 15 to 20C DT. If your a big overclocker on your GPUs, then shoot for 15C or lower. The VRMs on these new cards can be affected by temps. If you got a GTX 280 like me, don't worry about it, it's the 5970s and the 480s and other really hot cards that can have this issue.
So? How do you calculate all of this?
A bit of math, figuring out graphs, easy. LOL took me more than a few attempts to do it easy, but you can easily do it with help. Thanks to Martin (retired) and Skinnee we have the data. Bless them.
Let's go with my CPU standard of 250 watts and this link. Link to it please, go to page 4. Read it all when you get a chance.
http://www.skinneelabs.com/hwlabs-sr1360.html?page=4
This is a quality radiator with low fins per inch great for low RPM low noise fans.
Go to the second chart, Use the RED line, It's a good quality popular well performing fan at 1407 RPM. Good middle ground. Bottom of the chart find 250 watts, go up to the red line. WOW we have a 5.5 DT temp, very nice. Remember my comment about a CPU likes low DT but a GPU doesn't need it as much? Lets toss a 250 watt GPU into the same loop. Res-Pump-Rad-CPU-GPU.
Look what happens to the DT, it's over 11DT now, your CPU isn't happy anymore, but the GPU is just fine. In this case your under radded and need to split the loop or get your DT under control with more fannage, a better high FPI radiator choice AND new/more fans, or just more radiator square area.
In many situations splitting the loop is so much easier, but costs a LOT more. Keeping the CPU temp low on it's own loop, and having a smaller (relative to DT temps) loop just for the GPU. Sorry, but many of us do have a massive GPU setup these days. You wanna play right with watercooling? You pay.
This is where my earlier entry matters.
1. Your budget
2. Acceptable noise levels
3. What can you fit in your case
You can easily go past your budget once you start. It's amazing what a proper WC setup costs.
Lots start out with the wrong radiator type or much too little radiator. Some think they can live with the high speed fans, but end up buying another radiator and trying to fit it in the case, which brings me to #3. Many times you just have to accept your beloved case isn't going to work. Or your going to have to hang rads on the outside, or even make a seperate rad box. You can't trick physics and think you don't need all the radiators you really do.
In summary, do your homework, plan for your rig and the 1 year out rig. You see another GPU in crossfire? Plan now.
Your DT matters, worth the effort to understand.
Welcome to the much needed Watercooling Heatload Explanation.
A watercooled PC generates heat, some parts make massive amounts due the incredible calculations to give us what we crave. Realistic games, Folding for our future, and decoding DVDs for our own personal use.
I'm going to focus on two parts of your PC. The CPU and the GPU. These are the main hot parts we need to cool. I'll touch on a few other issues you need to understand as I hack my way through this.
I used to teach electronics to young folks, been water cooling for a few years, and I think I can help get the concept across to any new person looking to expand their knowledge and build a really nice rig. Understanding the big picture, answering the eternal Forum question, "What stuff do I need to cool my rig". I'll try to answer this.
Most importantly, I need to say, if it wasn't for all the testers who post scientific tests and not hack reviews this post wouldn't exist. These are people who for science and curiosity spent $100s++ of their own money and time building testing rigs, and COUNTLESS hours of their personal time to inform us, the uniformed public. I thank you Martin and Skinnee, you're an amazing part of our water cooling world.
Past the garbage, on to the important stuff.
Okay, you got an xx processor. What heat does it make under load? Heat is from the voltage and the amperage draw your CPU needs. Increasing voltage really increases your heatload as does your overclocks.
If a CPU uses 200 watts of power, about 80% to 90% will be lost as heat as the work is done in the CPU. It's deep electronic stuff, just go with it okay? You have to remove the heat.
You can express your required heatload in three ways.
1. Basic cruzin the web
2. Gaming
3. Benching for the best overclocks
Understand these three important things. All of them come into play.
1. Your budget
2. Acceptable noise levels
3. What can you fit in your case
Determining your heatload isn't a perfect science. You'll find numbers all over the place. From what you have learned from reading lots of info, Googling terms like "heatload i7 965, AMD xxx, Q6600 overclocked , etc. Reading 3-7 pages of Google, and following links within the Goggle links you should have an idea of what wattage you need to cool for your needs for your CPU and/or GPU.
CPU heatload
For example, I remember a Q6600 at 3.9 was 150 watts MAX. An i7 at 4.0 250 watts. Right now as I type my i7 965 stock is at 80 watts. My peak load is 340 watts, but for a very, very short time. So take the min/max with a grain of salt. These are max testing loads, so real world is a bit lower if you're a big gamer. I'm making a point, it's a lot of heat and you need to remove it. I use 250 watts as my stress wattage for my calculations on MY chip.
GPU Heatload
GPU's are a big issue now. Some are moving to watercooling, never done it before just because their GPU screams like a undead banshee when gaming etc. I have these neat links from another forum. From what others have said these folks did a TON of work, and is trusted. They were able to only look at JUST the GPU heatloads on many cards. No full system power, we all can do that with a wattmeter.
Bookmark it!
http://www.overclockers.com/forums/showthread.php?t=635806
Please, I ask you to attempt to understand your heatload before we move on.
How basic WC works in relation to heatload
We generate xx heat, the heat is transferred to the water. The cooler the water the more heat is transferred. As the water heats up its removed by the radiator. The more efficient the fan/radiator combination is, the cooler the water. The cooler the water, the cooler your parts. So simple.
Basic watercooling uses a pump, res, a block, a radiator, AND ambient air temps. Our water can be no cooler than the air temps. A room at 12C will keep the chips much cooler than a room at 30C. Remember that statement. Summers are much hotter and many back off on their overclocks in the summer. Funny thought, I just realized more people mention chilled water, mini fridges etc in the summer.
Finally to Delta T (DT) temps and why it's so important to understand them.
DT temps is the foundation of your WC loop. The better they are, the cooler your chips are. In water-cooling it's simply the difference between the ambient air temps and the water temp on the outgoing side of the rad. Room temps vs. water temps. That's it. You can't remove all the heat or can you go below ambient room temps.
When you boot up a powered off WC PC, the water temps AND your CPU are at room temp. You boot the PC up, the chip gets hot FAST. The water moves over the chip, it begins to remove heat, it goes to the radiator, SOME of the heat is removed. Not all can be removed, you have to know thermodynamics deeply (more than me) to know exactly why. The water begins to warm up slowly, and in time, the water reaches a balance, an equilibrium is reached. Heat is made and heat removed, the loop is stabilized. You change the room temp, the load, or your fan speed it needs to readjust. You increase your cooling system, the water WILL get cooler, better chip temps.
Water temps in a stabilized loop, amazingly is very little different anywhere in the loop. 2-3C difference between the radiator out temp and the CPU out temp changes little. Remember the water can't remove all the heat, just some, and some is transferred to the air. Your radiator size, effiency and fans play a big part in this. It's a system built on many parts and within the laws of physics, look at it that way. Every part effects the other.
Now that DT and loop stability is explained, let's talk about good DT temps.
A CPU loop needs good DT. Under 10C is just fine, getting closer to 5C is very nice and important if you want big overclocks. Getting under 5C is just overdoing it, unless your very xtreeme, need it for benching or just want to do it. On an average CPU loop, shoot for under 10C and adjust your overclocks to be fine, under the temps suggested by the makers.
A GPU Loop used to be fine with a 15 to 20C DT. If your a big overclocker on your GPUs, then shoot for 15C or lower. The VRMs on these new cards can be affected by temps. If you got a GTX 280 like me, don't worry about it, it's the 5970s and the 480s and other really hot cards that can have this issue.
So? How do you calculate all of this?
A bit of math, figuring out graphs, easy. LOL took me more than a few attempts to do it easy, but you can easily do it with help. Thanks to Martin (retired) and Skinnee we have the data. Bless them.
Let's go with my CPU standard of 250 watts and this link. Link to it please, go to page 4. Read it all when you get a chance.
http://www.skinneelabs.com/hwlabs-sr1360.html?page=4
This is a quality radiator with low fins per inch great for low RPM low noise fans.
Go to the second chart, Use the RED line, It's a good quality popular well performing fan at 1407 RPM. Good middle ground. Bottom of the chart find 250 watts, go up to the red line. WOW we have a 5.5 DT temp, very nice. Remember my comment about a CPU likes low DT but a GPU doesn't need it as much? Lets toss a 250 watt GPU into the same loop. Res-Pump-Rad-CPU-GPU.
Look what happens to the DT, it's over 11DT now, your CPU isn't happy anymore, but the GPU is just fine. In this case your under radded and need to split the loop or get your DT under control with more fannage, a better high FPI radiator choice AND new/more fans, or just more radiator square area.
In many situations splitting the loop is so much easier, but costs a LOT more. Keeping the CPU temp low on it's own loop, and having a smaller (relative to DT temps) loop just for the GPU. Sorry, but many of us do have a massive GPU setup these days. You wanna play right with watercooling? You pay.
This is where my earlier entry matters.
1. Your budget
2. Acceptable noise levels
3. What can you fit in your case
You can easily go past your budget once you start. It's amazing what a proper WC setup costs.
Lots start out with the wrong radiator type or much too little radiator. Some think they can live with the high speed fans, but end up buying another radiator and trying to fit it in the case, which brings me to #3. Many times you just have to accept your beloved case isn't going to work. Or your going to have to hang rads on the outside, or even make a seperate rad box. You can't trick physics and think you don't need all the radiators you really do.
In summary, do your homework, plan for your rig and the 1 year out rig. You see another GPU in crossfire? Plan now.
Your DT matters, worth the effort to understand.
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