Everyone has read on the internet people complaining of thermal shutdown security activation, YLOD as a consequence of repeated overheat problems.
In fact it seems that SONY has prefered silence to efficiency on its implemention of the PS3's fan regulation !
You might have tried the fan test on start up ? Well it will give you a noise reference when the fan is at a full 100% command, which is quite impressive and close to an helicopter !
So I thought, well let's see what SONY has really done in the fan regulation with some measurements on the PWM command Fan of a 60Go PS3, which is well none for having the biggest thermal problems of all models.
Ok, then I have the fan activation law on that model, then I said to me, well, if we're not happy with SONY's configuration why not doing our own manual fan command ?
Well, this is what this article is all about, and I will explain to you what measurements I've done, what design I've made and what are my conclusions !
Part 1 : 60Go PS3's fan regulation law : the PS3 probing
First of all what do we need ? :
- The fan command is done using a PWM signal whoseratio is modified to adjust the rotation speed. If PWM is 10%, fan rotation is slow and very quiet, if PWM is 90%, fan rotation is fast and very noisy. So we've got to measure the PWM signal, I used my oscilloscope.
- The goal of the fan is to evacuate a heat quantity depending on its speed rotation. The effect is on the internal temperature of the PS3, so I measured the internal temperature with a thermocouple associated with a multimeter. My goal was to have a image of the overall internal temperature, not the temperature of one or the other CPU.
- The third parameter that would have been interesting is the noise measurement (Decibel meter) that would have told us the highest PWM to reach to still ear the game playing ! But infortunatly I didn't found one.
So here we are, internal PWM and temperature measurements, in the real conditions, it means : PS3 closed and the measurement wires coming out of the PS3 to access them.
This picture shows where I placed the thermal sensor, right in the heart of it ! Between power supply and blue ray drive for the upper parts, and between the CPU and GPU for the lower parts. Then the wire goes out of the PS3 througt the hard drive location.
The PWM signal is probed on the Fan connector.
On the following picture we can see the measurements wires getting out of the PS3 :
And in the next picture here is all the experimentation :
On the left the 60Go "under test" PS3.
In the middle the multimeter with the thermocouple wire from the inside of the PS3.
On the right the oscilloscope with the PWM wire from the inside of the PS3.
Part 2 : 60Go PS3's fan regulation law : the measurements
The way it is done :
- As thermal process is slow, I defined a time base of 5 minutes between each measurement.
- I measured the temperature when the PS3 was off, to have the ambiant environmental temperature, which I remind you is a main parameter. The higher the ambiant temperature is, the quicker the temperature evolves and the higher it gets, increasing all risks !
- Then I powered on the PS3 and let it wait in the XMB to warm it up.
- Next, I insered the James bond Casino Royale Blue ray which is automatically launched and starts with some previews and other stuffs to get waiting in the film's menu. This will make the PS3 run in full HD mode which will be a medium stress for the PS3, but will let me do my tests on a long time as the PS3 will use the same calculation power all along the movie, so generating the same heat approximatively.
- First, I will use analog video output and then I switch to HDMI to see if it has some inpact on the parameters measured.
- Finally, I will use my only game "resistance" to get the PS3 more stressed and to see how measured parameters evoluate.
So here are the results :
The first conclusion is that the PS3's regulation doesn't change that much as it stayed at 27.5% during all the time I made the measurements, but the temperature changed only on a 3°C delta.
If we draw the parameters we get :
Part 3 : Manual regulation law : the explainations
I realized that I don't have a game that can really load the PS3 to get it really heat and reach higher temperatures.
But it is not that important as I can deal it in another way !
I know that the PS3 regulation keeps the température to 40-43°C with a 27.5% PWM.
Now that I can manually fix my PWM ratio, what will be the temperatures in the PS3 in the same conditions ?
I'll come to it, but let see how I made my measurement this time.
In the previous picture you can see that I've made a custom PWM generator with a PWM command by a potentiometer !
On the left a old DVD power supply that delivers the 12V power supply.
In the middle my little design.
On the right a PS3 fan system connected to my custom system.
That's how I made it work, so now I can drive the PS3's internal fan !
But first problem, extand the fan's wiring to reach the external command !
And now the overall measurement system !
Now I can make MY temperature control and measurements !
Part 4 : Manual regulation law : the measurements
To compare similar things I have to make the same measurement conditions.
- I made a ambiant temperature measurement PS3 off,
- I made the PWM modifications and measurement on the Blue ray movie James Bond Casino royale playing
- I have to start the PS3 with a close ratio to 27.5%, I will use 23.9% as my potentiometer is not that accurate !
- I increased the PWM ratio to make the temperature decrease.
Problem reached !!!
The PS3 shut down in thermal protection as I reached 40°C with a 23.9% regulation, so regulation was to low which gives us a rule to respect, the manual system shouldn't allow too low PWM ratios. As they are controlled manually, if the user does not pay attention the PS3 will shut down with shutdown protections, so a minimum PWM should be provided by the manual command.
- So I started over with a higher starting PWM ratio of 36.8%.
- Then I increased the PWM to see temperature evolve
- And finally I decided to go back in low PWM to see if system shuts down again, which didn't, so in order to not destroy the PS3 I stopped !
Here are the results :
And now, the most important of all, a drawing of the temperature law depending on the PWM command ratio !!
Now we can see that using a manual Fan command can really make us reduce the system temperature, but You'll have to know that the noise will increase too !
In my tests, temperatures variations are not that big, but in cases where temperatures get higher the result should be proportionals !
So YES, I have a design that can be added inside your PS3 to let you adjust the temperature and probably avoid the YLOD in time !
I will soon work on providing a small product dedicated to the PS3 to manually control the fan !