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post #11 of 36
Quote:
Originally Posted by Contagious Specialist View Post

Thanks for your input. I took all this into consideration while testing out cooling with my overclock.

Well after some overclocking I was able to get a stable 4.5 GHz at 1.4 volts, and 1200 MHz on the GPUs. After playing around with the fan speeds, I have a hard time getting the CPU above 65c even at the lowest RPMs my fans will do. The GPUs hardly ever break 43c. I feel like there is more left in the GPUs. So far I am happy with the pumps being controlled by the CPU, and leaving the fans at a very quiet 650-850 rpm manual setting. The only other changes I plan on making cooling wise is to spread the fans out more along the channels. I'm doing this because I'm moving the case fans back to Mobo control.

The bad news about all this is the Rheosmart 6 blew out this morning. I have my Lamptron Touch that I'm going to install and RMA the Rheosmart. I'll keep the Rheosmart as a backup, and use the Lamptron. I'm under the impression that I can add another GPU and my loop will handle it just fine.

Overall I think you're right. PWM can be a waste. My next idea was to control the fans on the first rad going to the GPUs by the GPU's PWM header. Full cover blocks will destroy this idea, but since I'm moving on to another computer to water cool with my extra parts, I'll try it on that build.

My 45/45 was at 1.275 w/ original BIOS, went up 0.05 with new one..... I saw temps of 74C at 46/46 and 1.38 .... Is 1.4 your setting in the BIOS or max observed ? I see a boost of 0.1 or more anytime AVX instructions hit the CPU .... and I find if doing CPU testing I gotta wait a long time for temps to stabilize. My GFX temps are at 39C at 1250 rpm.... 44C at max of 850.

I'm not saying PWMis a waste..... from a purely technical standpoint PWM is superior, however from a user experience standpoint, there is no difference whether you get to 850 rpm via PWM or VV .

My point is, would your user experience be in any way different if ya set the fans to an inaudible 850 rpm and left them there and forgone any fan control ? I think not..... but I still enjoy tweaking the curves just to see how low i can get em to efficiently cool the system. .... at 850 rpm (0.045 amps), you draw about 33% of the power / amps as at 1250 and at 650 about 15% (0.02)...so with 15 fans..... not like I need to worry about the power cost savings ..... 15 * 12 volts * (.045 - 0.020) = 4.5 watts when i slow down to 650.
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post #12 of 36
Unless you are using the Aquaero 6, PWM is not really the best way to control your rad fans and here is why:

If you base your fan speed on your CPU temps it will ignore when GPU temps are ramping up. And same in reverse if you base your fan speed on your GPU temps.
Best way to control rad fans is based on water temp, or dT. And only the Aquaero 6 allows you to do that wth PWM.

An other reason is this: imagine your CPU got from 30° idle to 60° loaded. It usually goes up pretty fast, while your water is still cool. You fans speed up abruptly and your water is still cool. Than you take the load off your CPU, and it cools back down to 30° idle. Your fans slow down with it while your water is still hot. So basically, PWM ramps up and down your fan speed more abruptly, and too early.

And some guys, like Martin of MLL, report there is sometimes an annoying humming sound.with PWM at mid range speed.

Rather than use true PWM, I suggest using the Lamptron CW611's 'fake' version of PWM. It will allow you to control all your fans and pumps, and LED's too if you want. And it can control your fans baded on water temp. And no huge dump of heat into your case with the Lamptron Iine.

Much better than the Sunbeam, or PWM for water coolers. 6 channels at 36W each for a total of 216W.

Mine should get into my mail box any day now.
Edited by PepeLapiu - 3/25/14 at 11:33am
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post #13 of 36
Thread Starter 
Quote:
Originally Posted by JackNaylorPE View Post

My 45/45 was at 1.275 w/ original BIOS, went up 0.05 with new one..... I saw temps of 74C at 46/46 and 1.38 .... Is 1.4 your setting in the BIOS or max observed ? I see a boost of 0.1 or more anytime AVX instructions hit the CPU .... and I find if doing CPU testing I gotta wait a long time for temps to stabilize. My GFX temps are at 39C at 1250 rpm.... 44C at max of 850.

I'm not saying PWMis a waste..... from a purely technical standpoint PWM is superior, however from a user experience standpoint, there is no difference whether you get to 850 rpm via PWM or VV .

My point is, would your user experience be in any way different if ya set the fans to an inaudible 850 rpm and left them there and forgone any fan control ? I think not..... but I still enjoy tweaking the curves just to see how low i can get em to efficiently cool the system. .... at 850 rpm (0.045 amps), you draw about 33% of the power / amps as at 1250 and at 650 about 15% (0.02)...so with 15 fans..... not like I need to worry about the power cost savings ..... 15 * 12 volts * (.045 - 0.020) = 4.5 watts when i slow down to 650.

1.400 is what I set the voltage to, AI Suite shows 1.405-1.435 IIRC (I don't have my notes on me). I'm still working on OCing, plus I got the Intel PTPP, so I don't mind frying the CPU if it's a bad clocker. I think tonight I'm going to shoot for 4.7. If that fails, I'll stay at 4.5, then try to slowly lower the voltage. I'm actually considering setting it to 4.3@1.3v because I personally prefer the voltage under 1.4.

Well, like you I enjoyed this little test. My mind was blown at how silent and cool my system runs with the fans being so low. I also made a small change to my loop (Inlet was going to the wrong res port so you could hear the water trickling) to quiet it down, and now I can't hear the thing.
post #14 of 36
Quote:
Originally Posted by PepeLapiu View Post

Unless you are using the Aquaero 6, PWM is not really the best way to control your rad fans and here is why:

If you base your fan speed on your CPU temps it will ignore when GPU temps are ramping up. And same in reverse if you base your fan speed on your GPU temps.
Best way to control rad fans is based on water temp, or dT. And only the Aquaero 6 allows you to do that wth PWM.

An other reason is this: imagine your CPU got from 30° idle to 60° loaded. It usually goes up pretty fast, while your water is still cool. You fans speed up abruptly and your water is still cool. Than you take the load off your CPU, and it cools back down to 30° idle. Your fans slow down with it while your water is still hot. So basically, PWM ramps up and down your fan speed more abruptly, and too early.

And some guys, like Martin of MLL, report there is sometimes an annoying humming sound.with PWM at mid range speed.

Rather than use true PWM, I suggest using the Lamptron CW611's 'fake' version of PWM. It will allow you to control all your fans and pumps, and LED's too if you want. And it can control your fans baded on water temp. And no huge dump of heat into your case with the Lamptron Iine.

Much better than the Sunbeam, or PWM for water coolers. 6 channels at 36W each for a total of 216W.

Mine should get into my mail box any day now.


Never mind, I'll repost when I have the pics to post.

Darlene
Edited by IT Diva - 3/25/14 at 12:47pm
post #15 of 36
Thread Starter 
Quote:
Originally Posted by IT Diva View Post

Never mind, I'll repost when I have the pics to post.

Darlene

Thanks, now I want to buy that for my computer. I live with the Lamptron touch for now, and give it a shot in a week or two.
post #16 of 36
Quote:
Originally Posted by PepeLapiu View Post

Unless you are using the Aquaero 6, PWM is not really the best way to control your rad fans and here is why:

If you base your fan speed on your CPU temps it will ignore when GPU temps are ramping up. And same in reverse if you base your fan speed on your GPU temps.
Best way to control rad fans is based on water temp, or dT. And only the Aquaero 6 allows you to do that wth PWM.

An other reason is this: imagine your CPU got from 30° idle to 60° loaded. It usually goes up pretty fast, while your water is still cool. You fans speed up abruptly and your water is still cool. Than you take the load off your CPU, and it cools back down to 30° idle. Your fans slow down with it while your water is still hot. So basically, PWM ramps up and down your fan speed more abruptly, and too early.

And some guys, like Martin of MLL, report there is sometimes an annoying humming sound.with PWM at mid range speed.

Rather than use true PWM, I suggest using the Lamptron CW611's 'fake' version of PWM. It will allow you to control all your fans and pumps, and LED's too if you want. And it can control your fans baded on water temp. And no huge dump of heat into your case with the Lamptron Iine.

Much better than the Sunbeam, or PWM for water coolers. 6 channels at 36W each for a total of 216W.

Mine should get into my mail box any day now.


Never mind, I'll repost when I have the pics to post.


OK, I found the post I was thinking of.

Here's what was originally posted here, with the following link to verify the statement about the 611's output.

http://www.overclock.net/t/1470452/pwm-pump-control-rive-be-limitations-and-lack-of-affordable-alternatives/30#post_21880552

I thought I posted the scope pics of the 611 output the last time we talked about Lamptron controllers and "fake" PWM. (see the link above)


While it is true that several of the Lamptrons have an 11KHz PWM component added to a fixed DC level base, the 611 does not do that. Actually, the FC9 doesn't do it either.

The 611 output is a purely variable DC voltage output.

It's really one of the very best of the controllers available excluding Aquaeros.

Look at the rear of the controller, and if you see the sizable caps and inductors, there's no effective PWM component in the output.


The real advantage of using a fan controller over the mobo/CPU temp, is as Pepe stated, that it allows you to use coolant temp, which while not as good as delta t, is still preferable to CPU temp alone, when you have a loop with included GPU(s).


Darlene
post #17 of 36
Quote:
Originally Posted by Contagious Specialist View Post

Thanks, now I want to buy that for my computer. I live with the Lamptron touch for now, and give it a shot in a week or two.

Here are some of yhe improvements over the Touch, which I also own.
- 6 more watts per channel.
- selectable lower and upper temperature limits.
- option to set each channel as fans, pump, or flow.
- reported ticking or humming sound by some with the Touch appears to have been fixed on the CW.
- from videos I have seen, I find the GUI easier to use and navigate.

To me, the CW611 promises to be THE best controller..... for the money anyways. I can't justify the extra 2-300$ the Aquaero 6 would cost just for those bells and whistles.
Edited by PepeLapiu - 3/25/14 at 3:17pm
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post #18 of 36
I don't undetstand Darlene
If the CW611 does not modulate the 12V, than how do you suggest it varies the output?
If it were actually undervolting the output, it would produce a @#%(! load of heat, no?
Could it be that the frequency is too high for your voltmeter to dissernate 9V from 75% of 12V?
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post #19 of 36
Quote:
Originally Posted by PepeLapiu View Post

I don't undetstand Darlene
If the CW611 does not modulate the 12V, than how do you suggest it varies the output?
If it were actually undervolting the output, it would produce a @#%(! load of heat, no?
Could it be that the frequency is too high for your voltmeter to dissernate 9V from 75% of 12V?



I didn't use a volt meter, I used an oscilloscope, frequency would not have been an issue.

Look a the pics in the post, you can see that the lower end FC3 doesn't reintegrate the pulse portion of the output, but that the 611 is a straight line, indicating that it does.

Essentially, the controllers with the caps and inductors on the PCBs reintegrate the pulses, so that the output is a smooth DC voltage, very much similar to how the PSU maintains a smooth DC output from a PWM switch mode design.

From the load's perspective, it can't tell, and it makes no difference, whether the voltage comes from a reintegrated pulse train or from a high heat producing linear circuit.


Darlene
post #20 of 36
Quote:
Originally Posted by Contagious Specialist View Post

1.400 is what I set the voltage to, AI Suite shows 1.405-1.435 IIRC (I don't have my notes on me). I'm still working on OCing, plus I got the Intel PTPP, so I don't mind frying the CPU if it's a bad clocker. I think tonight I'm going to shoot for 4.7. If that fails, I'll stay at 4.5, then try to slowly lower the voltage. I'm actually considering setting it to 4.3@1.3v because I personally prefer the voltage under 1.4.

Well, like you I enjoyed this little test. My mind was blown at how silent and cool my system runs with the fans being so low. I also made a small change to my loop (Inlet was going to the wrong res port so you could hear the water trickling) to quiet it down, and now I can't hear the thing.

Try Running RoG Real bench Open CL test and watch your voltages..... if you are under Adaptive control, I expect you will exceed 1.5 volts.


Quote:
Originally Posted by PepeLapiu View Post

Unless you are using the Aquaero 6, PWM is not really the best way to control your rad fans and here is why:

If you base your fan speed on your CPU temps it will ignore when GPU temps are ramping up. And same in reverse if you base your fan speed on your GPU temps.
Best way to control rad fans is based on water temp, or dT. And only the Aquaero 6 allows you to do that wth PWM.

An other reason is this: imagine your CPU got from 30° idle to 60° loaded. It usually goes up pretty fast, while your water is still cool. You fans speed up abruptly and your water is still cool. Than you take the load off your CPU, and it cools back down to 30° idle. Your fans slow down with it while your water is still hot. So basically, PWM ramps up and down your fan speed more abruptly, and too early.

And some guys, like Martin of MLL, report there is sometimes an annoying humming sound.with PWM at mid range speed.


Deja Vu all over again smile.gif Again, your reasoning is perfectly logical and well thought out ..... but there are different ways of looking at the issue and under the different scenarios, the best solution may vary. This is mainly due to the following:

-High end GPUs produce more than twice the heat of CPUs so in a twin GFX system, you are looking at a 4.5 to 1.0 ratio of heat produced. They can in no way therefore be considered equal contributors to the heat issue.
-In a WC loop, it's rare to see a GPU hit 50C .... 30C below where we start being concerned. OTOH, CPUs oft hit 75, 80C or more, well into the area which we get concerned.

1. First off, PWM is not relevant to the issue of temp control / fan speeds. Here's why .... if instead of using your CPU or CPU_OPT header which are PWM, you used the 3 or 4 pin MoBo Headers (These are variable voltage control and respond to the same CPU Temp criteria), how would things change with respect to the fans ? Nothing changes with regard to speed control. If you stop using PWM but your fans are still responding to CPU via voltage control signal, eliminating PWM won't change anything. There are some fans that have a particular noise to them but a) the easy solution is just avoiding them, b) you can control 3 pin voltage controlled fans in response to CPU temps with PWM header and Phanteks PCB eliminating any PWM noise as the PWM signal never reaches the fans or c) ya get no noise using VV fans and MoBo CHA headers.

2. As for the CPU versus GPU issue, you can connect to the fan header signal from the GPU if you want to control the Rad fans downstream of the GPU separately.
http://www.quietpc.com/gel-pwm-vga-cable

3. As we discussed before, even with synthetic GFX benchies have you found any of them where the GPUs only heat up ? In any demanding current game, my CPU temps are mid 60s whereas the GPU temps are in mid to hi 30s. While in theory, the logic is totally sound, in practice the problem never materializes. Even in Furmark which I have running right now, w/ CPU running at a mere 40 watts, the CPU Core temps hit 53C (hottest core)..... (51C on Valley)..... while the GPU temps stabilize at 44C w/ 850 rpm fan speed limit .... If there is something you can run on a PC that gets the GPUs hotter than the CPUs on a WC build, I haven't seen it. So while you have a laid out a perfectly logical solution to the problem of the GPU being hotter than the CPU, I don't think that is a problem that anyone has ever actually experienced.

4. As for the starting / ending early thing .... again, you have a perfectly logical solution. But again, is there a "problem". Due to the thermal mass of the loop, how long it takes ya system to stabilize will depend on how much coolant is in the loop and to a lesser extent the thermal mass of everything in the loop. But if ya fans go from 550 rpm to 850 rpm, yes the geek in me says that I have made my system more efficient ..... but 3 minutes after P95 shutdown, my fans are still at 710 rpm ...at 6 they are at 617 rpm..... the FanXpert2 Software also provides for a 3.5 minute spin up / spin down time and even lets you program in a fan stop point.

5. With CPU only loads, my coolant temps don't really change that much .... Under P95, with an ambient temperature of 20.5, my coolant temp is 25.7 going into the rad downstream of the CPU and 25.2 coming out of the rad upstream of the CPU ....a Delta T across the rads of only 0.5C....my worse core temp peak was 84C (AVX loads and Adaptive). If I was controlling based upon water temps, I'd really be concerned about having more pump and fan speeds when CPU temps are that high than when delta T = 5C.

In summary, everything you said (except for the PWM part), makes perfect logical sense ...... in theory. But in a practical sense, I don't think the problems which the solution addresses arise all that often (if ever) and, if so, alternatives exist which provide equivalent functionality.

a) PWM and VV are just two different means of accomplishing the same thing. To control ya system via CPU temperature with PWM, connect what you want to control to one of the two PWM headers on the MoBo (CPU or CPU_OPT). To control ya system via CPU temperature with variable voltage (VV), connect what you want to control to one of the many 3 or 4 pin headers on the MoBo (CHA or OPT).

b) If you wanna control fan speeds on different rads separately, you can use the fan headers on the GPUs instead of the MoBo. Not something I'd recommend

c) I have yet to find any program that I can run that drives my WC'd GPUs to a higher temp than my WC'd CPU. As my GPU temps have never risen above 44C with fans running, having the fans respond to any change of temps is of no consequence. Running at fixed minimum speed still keeps them > 30C below any temp I'd be concerned about.

d) Ramping fans up and down is provided for via the pump curves and setting ramp up and ramp down speeds. However, if you ignore them, what is the impact on the user experience if the fans did not start and end early ? Saving 4.5 watts for 3 minutes say 6 times a day ?

From a power cost perspective .... 4.5 watts x 3 min / 60 min per hr x 6 times 1 kw / 1000 watts x $0.10 per kw/hr = 5 cents a year

From a noise perspective ..... in my case there really is 0 impact as my fans are dead silent from 900 rpm down. You you don't hear anything at any of those speeds and since nothing has as yet made me exceed 850 when fan curves are controlling, there is no impact. However, if you went light on rads and made up for that with high speed fans..... you would be able to observe a difference.... that being a 3 hour gaming session would only have perhaps 2 hours and 57 minutes of observable noise.

I have easily spend 50 - 60 hours running tests, tweaking fan curves and the like but must honestly say, other than loads of geeky enjoyment, it has not impacted the system or the user experience in any observable way. If set the fan curves to a fixed 850 rpm, the only effect is that they would be running faster than they need to.... there is no observable noise impact and the power savings is barely measurable.....so, one could argue, what's the point ?

Many MoBos today come with OPT thermal sensors. Asus for example has 3 OPT thermistor inputs on the M6F and you can read the temps in the BIOS and in the AISuite software. They also provide 3 OPT fan headers. I do think at some point in the very near future we will see those OPT thermistor inputs and OPT fan headers linked via the FanXpert software.

e) If I was controlling fan speed based upon Delta T and my worse case was 10C .... say:

Delta T = 1C = 25% fan speed
Delta T = 2C = 25% fan speed
Delta T = 3C = 30% fan speed
Delta T = 4C = 40% fan speed
Delta T = 5C = 50% fan speed
....
Delta T = 9C = 90% fan speed
Delta T = 10C = 100% fan speed

What I would have is my fans running very close to full speed (90%) and in the audible range at 9C under huge GPU load ..... do I really care whether temps are 39C or 44C if I gotta pit up with fan noise ?

OTOH, my fans running at 50% speed (Delta T of 5) with a max CPU core temp of 84 under a heavy CPU load and I'd be very much want it to be in the 90%+ range at that temp. At 84C, unlike the GPUs 40ish temp, I am starting to get concerned about temps. Instead of 0.5C across the rads and a max coolant temp of 25.7 at 50% speed.... I dropped 8C to 76C on CPU temps and max coolant temp was 24.6 at 90% speed

To summarize, I don't think there is a "best way" to control fan speeds in all circumstances..... there is a best way for each of several conditions and circumstances.

-Control based upon GPU is rather meaningless as under any conceivable circumstance, your GPUs are in no danger of overheating.

-Control based upon CPU does make sure that the only component in danger is always of primary concern..... CPU testing does result in hi CPU temps and meaningless GPU temps and GPU testing, even with GPU benchies still produces significant CPU temps. Under any circumstance I have experienced with a water cooled system, GPU's never exceeded CPU temps.

-Control based upon water temps will work well in high GPU loads and in mixed load situations but will be less than ideal under CPU only loads because the CPUs thermal outputs is typically only 15% or so of the thermal load a twin GFX card system is designed for. the control system will therefore be indifferent to hi CPU temps because while CPU temps will be bear max, the system coolant temps will be scarcely be above idle....since stopping P95, I went from 24.6 max coolant temp @ 90% fan rpm (25.7 @ 50%) to just 24.3

Its that last scenario that is troubling .... with fan speeds based upon coolant temps, how do I get my fans to 90% at 24 - 26C (CPU temps at 80) under a CPU test ..... and then at an inaudible speed when gaming with the coolant temps at 30C, CPU temps are 65C and GPU temps are at 40C ?
Edited by JackNaylorPE - 3/26/14 at 12:39pm
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1 x Swiftech 35x2 w/ Heatsink and NB Fan EK -MultiOption RES X3 250 White Acetal Reservoir 5 x PH-F140SP_BK_BLED + 5 x PH-F140SP_BK E22 Rigid 10/12 Acrylic Tubing and Bitspower Ma... 
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2 x Reeven Six Eyes Fan Controller Windows 7 64 Bit Professional OEM ASUS VG248QE Black 23" 144 Hz Monitor Logitech G19s 920-004985 
PowerCaseMouseAudio
Seasonic X-1250 Phanteks Enthoo Primo Ultimate Chassis Asus RoG GX950 Laser Mouse  Logitech Z5500 
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