The "Undervolting" Guide

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This guide is written by flipfire along with the ideas, knowledge and help of other members. This guide covers most bits about undervolting while keeping it simple and accurate as possible. This method should also work with supported processors as the concepts outlined remains the same.

For this guide, I will be using a Santa Rosa T7500 processor on Vista using RMclock v2.35

I recommend undervolting to anyone with enough confidence and knowledge to do so. The benefits easily outweigh the risks. I dont see why one shouldn’t do this for a cool adn better notebook experience.

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What is Undervolting?​

Undervolting is a process which reduces the excess "voltage" given to the CPU using a software. This is widely used as a cooling solution and in my opinion more effective than any other cooling solution available (thermal paste, cooling pad, etc) at NO cost. Results can vary from 5c up to 30c drop in temperature, most will achieve an average of 10c.

Undervolting will NOT compromise performance at all. Underclocking and Overclocking (clock speeds) is whats responsible in regards to performance. Benchmarks will also prove that performance remains the same. Most beginners usually think and assume undervolting will sacrifice performance but they are wrong.

So you’re probably wondering how this works out and why Intel/AMD didn’t do this before hand..WHY? HOW?

Not all processor chips are built equally. Each individual processor have different voltage tolerances. Instead of Intel tuning each chip's voltage individually for the lowest voltage possible and risking instability, they made a fully stable standard voltage for all chips to run on. The problem is this standard factory voltage they put is quite high. Undervolting takes advantage of this by reducing it to the right amount.

This is also why some people can undervolt more than others even with the exact same model processor. It’s like the same concept for overclocking, some can go higher, some cant. Unlike overclocking, Undervolting will not void your warranty or damage your hardware.

Bottom line is.. There is no catch to undervolting.

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*Advantages of Undervolting
- Cooler CPU (5 to 20c cooler)
- More battery life (15-30mins more)
- Less Fan noise & activity
- Longer overall notebook life
- Eco-Friendly​

By reducing the voltage fed to the CPU, it will run much cooler. It will also draw less power from the battery which can give you an extra 10-30+mins battery life depending on the degree of the undervolt. Also a cooler CPU means less fan activity which again points to more battery life and less fan noise. A Cooler CPU could also lead to a cooler GPU if they share the same heatsink/fan. It is common sense that a cooler running notebook will last longer than a warmer/hotter counterpart. Heat is the killer of electronic parts.

*Disadvantages/Risks
- BSOD (Blue Screen of Death)​

You will get a BSOD at the very most if the voltages are too low. This is why we do a stability test to make sure we get no BSOD's. If the voltages are setup properly you shouldn’t get any at all. A BSOD seems to be the only risk for undervolting in my experience. So make sure everything is saved before you do anything. I dont wanna be responsible for any loss or hoo-haa's.

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You will need to download these programs (Dont install RMclock yet). Click to go on download page
- RMclock v.2.35 - (CPU clock utility)
- ORTHOS CPU Loader - (Used to stress the CPU and test for stability)
- HWmonitor - (Choose between 32/64bit on top left corner)

(ORTHOS and HWmonitor do not need to be installed . They are just .exe programs)

1)***Checking Max temps before Undervolt***​

Firstly, We need to find out how hot your CPU gets when under load to compare what undervolting can achieve.

i) Open HWmonitor. It will show the CPU/GPU/HDD's maximum, minimum and current temps. Today we are only going to be looking at the CPU core temps. I recommend using HWmonitor because its one of the best temp programs and its accurate but others will work too.

ii) Run ORTHOS CPU Loader. This handy program will simulate full cpu load for both cores.

iii) Click on the Start button and let it run for 10mins. Watch the temps shoot up to about 70-90c.

iv) Once its done stressing the CPU for 10mins, stop the program and record the maximum temp.

-I managed to get a scorching temperature of 79c.

2) ***Installing and setting up RMclock*** ​

Note: Vista x64 users will need to download the signed 64bit drivers down below to make RMclock work.

i) Unzip/Install RMclock into your notebook

ii) Run RMclock

iii) Click on the "Advanced CPU Settings" tab. The latest version of RMclock should automatically detect your CPU. If it doesn’t then click on the "Mobile" radio button near the bottom and tick "Apply these settings at startup". Now hit the Apply button

*AMD users need to tick P-State Transistors for a better undervolt



- If it asks you to restart the program, do so. After it has restarted go to the "CPU info" tab. Double check its showing the correct processor you have. On this page you will also see alot of digits moving up and down about your CPU.

3)***Setting up Profile***​

i) Double click on the Profile tab then click on "Performance on Demand" sub-profile.

- Tick "Use P-State Transitions" for both AC Power and Battery
- Tick all the index boxes possible, Make sure to scroll down and click the others
- Click Apply when all done.



Now we head back to the Main Profile page....

ii) Change the current profile in the drop down box to "Performance on Demand" for both AC Power and Battery

-Make sure all the index boxes are ticked. If you have SuperLFM or IDA i suggest leaving this out for the meantime. See down below later on for what these features do.

iii) Untick "Auto Adjust intermediate-states VID" near the bottom and hit the Default button. Your factory voltages should now show up. Click Apply.

4) ***Undervolting***​

In the main profile page, you will see different multipliers and voltages. What are multipliers?

Multipliers are incorporated with Intel SpeedStep Technology (see down below for full definition). Instead of the CPU running at full power all the time, multipliers are used to dynamically lower the clock speeds to make the CPU run more efficiently.

The more CPU power you need, the higher the multiplier your CPU will use. The higher the multiplier, the higher the corresponding clock speed will be. The higher the clockspeed, the more voltage it requires to run (vice versa)

i) First, We are going to start lowering the highest multiplier's voltage which is the 11x multiplier for me.

-Most people should be able to lower it by at least .100v to begin with the initial testing then slowly decreasing it from there on

ii) Always click Apply so the new voltage can take effect then do the stability test below. Keep doing this everytime you lower the voltage

5) ***Testing Stability*** (make sure all work is saved!)​

i) Open ORTHOS and HWMonitor again. (we will now see how much cooler it is)
ii) Go to the "CPU info" tab of RMclock (you can also watch the temps and stats here).
iii) Set the test type to "Small FFTs - stress cpu" to concentrate the test to the cpu.
iv) Run ORTHOS stress test for 45mins or more

- If it doesn’t crash when the stability test is done then you can go lower. I suggest lowering by .025v at a time till it BSOD or gives a warning error.

*If you get a bluescreen - then you have reached your limit and the voltage is too low. Once it restarts from the BSOD, it should revert to the last stable voltages. Keep a record of the good/bad voltages on paper.

*If you get a warning or hardware error from ORTHOS - Your voltage is also too low. Raise your voltage and try again.

-Once you have found your unstable voltage, i suggest raising the voltage up by 2 steps. This will put a safe margin away from your unstable voltage to ensure stability

**Its normal to get a BSOD or error at some point so dont freak out. It wont do any hardware damage.

**Most people are able to achieve .150v to .250v less than their default voltages for the highest multiplier. Again, it all depends on your processors tolerances.

6) ***Results***​

After several changes and stability tests i was able to lower it to 1.100v that’s .150 volts less than my standard voltage (1.250v). My undervolt isn’t as great compared to how low others can achieve but it has made a significant difference.

My max temps before undervolting was a scorching 79c now it is only 67c! That’s a big 12c shaved off at the cost of nothing.

I cannot accurately calculate how much extra battery life this will give cause of too many variables. I can only estimate about 15-25mins by perception as i havent got proper benchmarking programs and monitors. From what other users have posted, they saw an average of 10watt difference which should reduce the strain on your hot power adapters.

When you have found your optimum voltage settings, I suggest doing a further 3 hour stress test (when you have spare time) to make sure it is 100% stable.

Once you have made sure this voltage stable, you can now choose to make these settings run at startup:

Go to the Main Profile page > On the drop down box for startup choose "Performance on Demand" > Hit Apply

Now go to Settings page > Tick "Start Minimized in Windows Tray" and "Run at windows startup" > Hit Apply

To show your CPU temps in the Taskbar/System Tray > Right click the RMclock wheel icon and click "Show CPU Temperature"

TA-DA! Enjoy! Watch your notebook run significantly cooler

Side Notes:
-RMclock cannot recognize CPU's with half multipliers. It will round off to the nearest whole number thus downclocking. T8100/T9300/P7350/P8400/P9500 will underclock by 100mhz~
-The undervolt will only be in effect when RMclock is on.
-The latest CPU-z is bugged and will show incorrect voltages, use v1.41
-If you untick a box in the Main Profile page, you will need to retick them again in the 'Sub-Profile' page
-If your CPU is overclocked, make sure you undervolt when it is OC'd, so you can find the optimal voltages of the OC'd speeds.

7) ***Lowering and Testing Other Multipliers voltages***​

To make the most out of Undervolting, you can also lower the other multipliers to its optimum voltages. So far we have only set and tested the max multiplier. The lower the multiplier #, the less voltage is needs.

To do the stability test on the other multipliers we will need to disable the highest multiplier by Unticking it in the Main Profile page (11x multiplier for me) then clicking Apply. This will stop the CPU from using this multiplier meaning the 10x multiplier meaning this is the highest speed your CPU will reach. Each multiplier corresponds to a clock speed 11x is 2.2ghz, 10x is 2ghz, 9x is 1.8 (for my CPU of course)

Now you know the drill...
1) Lower the voltages slowly
2) Run ORTHOS test for 45mins
3) Double check in CPU Info page or CPU-z that its stressing and maxing out at the correct multiplier
4) Find the optimum voltage
5) Move on to the next multiplier by unticking the higher multiplier profile page then back to step 1

You do not need to test the lowest multiplier (idle) because we cant change/never changed the voltage. This voltage will always set at a stable voltage

Its a time consuming process getting the optimum stable voltages for every multiplier but it pays off in the end.

Note: After your done, make sure you re-tick the multiplier boxes in the "Main Profile" page then "Performance on Demand" sub-profile page, If you dont your CPU will be majorly handicapped

The lower the multiplier #, the more sensitive the voltage is to a BSOD! Most BSOD's from undervolting are usually because of unstable lower multipliers. For first time undervolter's i suggest leaving a small voltage margin from your unstable voltages.

Quicker Alternative: If you dont have to time to stability test every multiplier there is another way. Ticking the "Auto-adjust Intermediate States" box will fill in all the multipliers in between your Idle (6x) to your highest multiplier accordingly. It seems to work well for at most cases but theres no guarantee that all the multpliers are 100% stable, since it just fills it in mathematically. It seems to work fine for most people though.

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Extra! Locking CPU to full speed/throttle​

RMclock offers different power profiles. The Maximal Performance is profile allows you to choose only 1 multiplier which will be locked at that multiplier/clockspeed.

This profile is great for gamers, certain scenarios where full cpu is needed and people having issues with Speedstep not switching properly. I only recommend using this profile when the notebook is plugged into the AC adapter because it will increase the drain on your battery.

Locking the CPU will reduce the small throttle lag you get from the usual dynamic multiplier switching. It improved my PCMark05 points when i locked it to full speed.

To lock the CPU to full speed:
i) Go to the Maximal Performance Sub-profile page
- Tick 'Use P-State Transition'
- Tick the multiplier you want to lock the speed at (Choose the highest index #)
- Click Apply
ii) Go to the Main Profile Page
- Select the Maximal Performance on the drop down boxes for AC Power Current and Startup
- Click Apply

If successful, you should notice the RMclock wheel icon in the system tray turn completely red. This signifies the speed is locked to maximum speed.

This configuration will only lock the CPU when you are on AC power. When it is unplugged, it will change to dynamic switching (Speedstep) for improved power consumption. You can also choose to underclock the CPU when using the battery for longer battery times.

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Extra! How to Underclock CPU using RMclock​

The current profile we have is dynamic which means it will only use up as much cpu power as it needs. Underclocking is only useful if you want to completely limit your CPU's top speed for certain specific reasons. Obviously your notebook will run relatively slower depending on the underclock.

If you have tested the 'other multipliers' above this and haven’t realised it... then you actually have unknowingly underclocked. By unticking the index/multipliers in the Main Profile page, you are disabling the multiplier/speeds the CPU can use. So its common sense that we untick the higher multipliers. Make sure to hit Apply and check the CPU info page

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What is Intel SpeedStep Technology?​

"SpeedStep allows the clock speed of a processor to be dynamically changed by software. Running the processor at higher clock speeds allows for better performance. However, when the processor is run at a lower speed, its core voltage can be reduced, allowing for reduced power consumption and heat dissipation."

In basic terms, instead of the CPU always running at full throttle all the time, speedstep dynamically lowers the clock speed using multipliers to make the CPU run more efficient. It will only use up as much CPU power when it needs too.

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What is SuperLFM and IDA?​

SuperLFM stands for Super Low Frequency Mode. This ingenious feature lets your processor idle at an even lower clock speed by dynamically cutting the FSB in half. In turn, means even lower clock and voltages thus more battery life and efficiency. On a T7500 i was able to make my CPU idle on 600mhz@0.850v instead of the default 1200mhz@0.937v . This feature is only available on the Santa Rosa Platform, T7xxx CPU's and above using the v2.35 of RMclock.

To enable SuperLFM, Go to the Main Profile page
1) Tick Index 0 which should be named SuperLFM
2) Set the FID to 6x instead of the default 8x. The default voltage is usually the correct one. If its not, then try putting it down to the lowest voltage possible. The lowest voltage varies from your CPU model
3) Go to the 'Performance on Demand' sub profile page and make sure the P-State Transition box for Index 0 is ticked.
4) Hit Apply after all done, then check the CPU Info page for the superlow frequency and/or voltage

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IDA stands for Intel Dynamic Acceleration. Basically it uses one core while the other rests. Im not really a big fan of this feature because its buggy and the gains are negligible so i just kept it turned off. This will probably help explain it better.

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RMclock for Vista 64bit users​

A digitally signed/secure driver is required for RMclock to run on Vista 64bit. We have finally acquired a digitally signed driver for RMclock!

Here is the link for the signed RTCore64.sys driver: (Virus free and tested)
www.flipfire.net/download/rtcore64.zip or here

Download and extract it to your RMclock folder and overwrite the old driver.

(NOTE: This driver is only for Vista 64bit. The XP 64bit drivers are already included with the standard installation)

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Other handy cooling solutions can be found HERE by the NBR cooling team

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search tags: undervolt undervolting undervolted underclock undervolt guide
Id like to give credit to blackbird (i followed his guide on my first time), John Ratsey for the signed x64 drivers, Rightmark, CPUID, ORTHOS and www.graphxservice.com for the banner and anyone else who i didn’t get to mention. (Let me know)


Did you like this Post? Did you learn something from it? Then vote for it in the NBR Amazing Content Contest

 

yay! Great job flip. Now i can link to this page instead of trying to explain it myself.

+reps

 

Great stuff, rep for you. Looking forward to more info.

 

An excellent guide. I have been undervolting for several years. Less heat also mean less fan noise.

I just keep the CPU stress test running and drop the voltage at the maximum multiplier at about 1 step every 15 seconds starting at 1.10V (for Intel Core / Core Duo). This very quickly finds the voltage which is definitely unstable and BSODs (keep a recod of the voltage as you drop it). I then put the voltage back up two steps and run an overnight stress test.

John

 

Nice work! Although I still can't give you rep points.

 

Pics of my T5300 undervolted to .950V running on Balanced Max clock 1.74 GHz
Max Multiplier 13x
http://i32.tinypic.com/1z3s7l0.jpg <--temps/CPU clock 800Mhz
http://i25.tinypic.com/24wawsg.jpg <--management settings
http://i27.tinypic.com/20kxfr4.jpg <--Recommended Index and volt setting. Keep computer on "Performance on Demand" for optimal power saving.

 

Thats underclocked to 800mhz@0.950v . Thats major cpu handicap, undervolting isnt really making any gains at these settings

I suggest applying these settings under the "Power Saving" profile for superrrr battery savings

 

Good stuff, wish I had of known about this sooner!!

Thanks

 

I put it up to max clock when I'm running applications like Photoshop, but for using microsoft office, watching youtube, browsing the internet, and watching non-HD videos it works fine. I've had it clocked like this for quite a while now.

 

FLIPfire
maybe you should make a note saying that

"If the person overclocks his Cpu when gaming he should use that speed as the basis of his undervolting since overclocking when you already have a a decent undervoltage setup will give you more trouble".

(Please make the words more sensible)