Undervolt explained, Overclocking voltage.

Undervolting, or undervolt means using a lower voltage during over clocking.


All modern IC use a fixed voltage to do their work. If they need to do more work they draw more current at the same volts.

1.2v and no work = 1.2v
1.2v and working hard = 1.2v

Each of the above assumes infinite current.

The over clocking voltage dilemma starts.

A CPU is rated at a meridian voltage based around a minimum and maximum safe voltage.

As reactive loads they do not conform to R=V/I in the sense of a simple resistance. The apparent resistance is reactive to need, not voltage. CPU’s are programmed to know the voltage for a given frequency given infinite current.

More, CPU IC’s are not voltage regulators. Raise the voltage and the same frequency CPU will just dissipate, in heat, the excess. Your CPU will get hot. Try it. Up your voltage but not your clocks.

So, here we are. What is the correct voltage?

Specification of the CPU put it clearly at 4.2Ghz 1.4250v

Manufacture error?

3.9Ghz 1.3850v +_ 10% = 4.2Ghz ~1.4040v


AMD RADEON R7 360 safe overclock.

The AMD RADEON R7 360 comes in many forms. There is no official reference.

Pretty standard form:
GPU clock: 1000Mhz
RAM clock: 6400Mhz

So let us see what is out there.

Gigabyte GV-R736OC-2GD
GPU clock: 1200Mhz
RAM clock: 6500Mhz

All good, now, we will take ASUS AMD R7 360 as an example, as they have 2 revisions of the same model.

ASUS R7360-OC-2GD5
GPU clock: 1070Mhz
RAM clock: 6500Mhz

R2: (R2 must be better right?)
ASUS R7360-OC-2GD5-V2
GPU clock: 1070Mhz – 1090MhzOC
RAM clock: 6000Mhz – 6020MhzOC

What happened to the RAM clock on the R2?


We can see some manufacturers feel confident supplying 1200Mhz GPU’s, and 6500Mhz RAM using the same parts.

Checking the ASUS GPU Tweak tool I could take the RAM to 7500Mhz and GPU to 1250Mhz on a R2 card.

Looks like the R2 card was made so the tweak tool could have more perceived impact. Or with the R1 card over clocking was much more dangerous and needed headroom?

OK, on to the safe overclocking.

This GPU will run all day 1100Mhz 1.225V
Ram will run all day at 6200Mhz with stock cooler.

No voltage overclock needed and not beyond any specification of the GPU or RAM.

Always put power target at 110%. even at stock.

If you want to push it,
GPU 1150Mhz 1.255v
RAM 6400Mhz

Your temps will increase, depending on your card and cooler. Make sure the temps stay below 90C

Anyone with 1200Mhz GPU clock card, please do let me know the GPU Voltage for addition and reference to this article.

Note the GDDR 5 RAM chips are rated at higher frequencies without voltage increase. Simply current and so heat.


Kingston Hyper-X Blu 1600 1.5v safe overclock. Perfomance boost without overclock

Kingston Hyper-X Blu 1600 1,5v RAM come with very conservative settings.

You can safely over clock this RAM without going outside the frequency and voltage specifications.

First off, you need to make sure the RAM is getting the 1.5v it is supposed to be. My MB reported 1.47v when left at auto. The max rating for this RAM is 1.575v, the correct operating voltage is 1.5v. We do not want to increase the voltage above the correct operating voltage, just make it correct.

Let us fix that.

find your tool of choice to show the actual voltage, even the MB status will show actual v set.

Increase or reduce RAM voltage in your Advanced Voltage settings until you see the reports matching 1.5v. I have set 1.53v (+0.03v) and shows 1.50 in sensor readings. This is still well below the 1.575v max rating, so even in error of the sensors I am safe the RAM is now getting the correct voltage and maybe even a little extra.

For safety, make sure you never add more than .05v in case your sensors are way off.

Disable XMP profile, then increase RAM multiplier. Your target is the rated 1600Mhz.

change RAM timings from 10,10,10,35 to 9,9,9,24

your done, 8% ram speed increase without any frequency or voltage overclock.


AMD FX 6350 safe overclocking. Perfomance boost without overclocking.

How to get better performance without going outside specifications

AMD 6350


Under load: 3.9Ghz Vcore=1.3875
Idle: 1.4Ghz Vcore 0.8750v
Idle Boost: 4.2Ghz Vcore=1.425v

Note that under load the CPU does not use boost. Only from idle for short durations will you ever get 4.2Ghz clock.

Let us fix that.

In your BIOS,
Disable ‘Core Performance Boost’
Change your CPU clock ratio to 21 = 4.2Ghz
Set CPU Vcore to ‘normal’
Set Dynamic Vcore to +0.0125

Now your running at 4.2Ghz with Vcore 1.404v, under load, with lower voltage and temperatures than stock 4.2Ghz Vcore 1.425v on rare boost. On idle you still get 1.4Ghz clock at a slightly increased 0.880v Vcore. A non issue.

Over 12 hours at 100% CPU usage gave CPU temp 49C, with MB VRM of 72C. ~2C higher than stock settings at 3.9Ghz for the same 12 hours.

Simply setting multiplier to 4.2Ghz would have the CPU running at 4.2Ghz at 1.425v and temps approach 55C MB/85C VRM fast, due to the 1.425v auto setting.

If you do want to go over specification then with this method you could raise to 4.3Ghz or 4.4Ghz while only raising Dynamic Vcore up to the rated 1.425V. I will leave that to you, but keep an eye on CPU temp and MB VRM temps. CPU should not go more than 60C and MB VRM no more than ~90C.

MAX VRM temp for my MB is rated at 110C before throttling.


Linux Mint 18, Ubuntu 16.04 AMD Radeon open source video problem, vainfo error

Getting poor video playback or video problems using Linux Mint 18 or Ubuntu 16.04 and the open source AMD Radeon driver?

You will probably notice your vainfo shows an error:

libva: VA-API version 0.32.0
libva: va_getDriverName() returns 0
libva: Trying to open /usr/lib/dri/r600_drv_video.so
libva: va_openDriver() returns -1

install vdpau-va-driver
sudo apt install vdpau-va-driver

Now add LIBVA_DRIVER_NAME=vdpau to /etc/environment and reoot.

now all should be good and vainfo should show something like
libva info: VA-API version 0.39.0
libva info: va_getDriverName() returns 0
libva info: User requested driver 'vdpau'
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/vdpau_drv_video.so
libva info: Found init function __vaDriverInit_0_39
libva info: va_openDriver() returns 0
vainfo: VA-API version: 0.39 (libva 1.7.0)
vainfo: Driver version: Splitted-Desktop Systems VDPAU backend for VA-API - 0.7.4
vainfo: Supported profile and entrypoints
VAProfileMPEG2Simple : VAEntrypointVLD
VAProfileMPEG2Main : VAEntrypointVLD
VAProfileMPEG4Simple : VAEntrypointVLD
VAProfileMPEG4AdvancedSimple : VAEntrypointVLD
VAProfileH264Baseline : VAEntrypointVLD
VAProfileH264Main : VAEntrypointVLD
VAProfileH264High : VAEntrypointVLD
VAProfileVC1Simple : VAEntrypointVLD
VAProfileVC1Main : VAEntrypointVLD
VAProfileVC1Advanced : VAEntrypointVLD

[update]This does not work with Radeon R7 360 and is not needed[/update]