nvidia GPU overclocking totorial

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#1
By default your GPU should use a voltage-frequency curve that makes the card fully stable. Typically however there is a very big margin allowing the frequencies the card runs at to be drastically increased. To do so download msi afterburner and click "control" and "F" on the keyboard.
tuf3090oc.png

As we see here the frequency could be increased 300mhz at low voltages but just 90mhz at high voltages. This will be different with another card even if it's the same model, you are only guaranteed stability at stock settings.

Typically the voltage and frequency of an nvidia card will fluctuate based on how much power the card uses. That power-limit can be changed up to some maximum.

The voltage-frequency curve will also be affected by temperature. For that reason you want to achieve a stable temperature by using a steep custom fan-curve (such as between 76 and 86 °C).

Stability testing
You can lock the card at one particular voltage & frequency by pushing Control L. You can also just run the card as normal and use geforce experience to monitor the frequency of the card, then if it crashes you see what the unstable frequency was and you then need to adjust that.

In order to test the stability at the higher voltages you should maximize the power-limit, that however is often not enough to test the full curve. What you will probably need to do is to decrease the resolution (such as via DLSS) so the game will be unable to load all GPU-cores, if the game remains GPU bound the frequency of the card will be pushed up due to the boosting headroom.

You can verify that the game is GPU-bound by looking at the GPU-power, if it is at the maximum you are GPU-bound even if your GPU-utilization is 25%.

Capping the voltage
As you see there is diminishing returns when it comes to higher frequency from higher voltages. It might not be worth the extra power-consumption just to get 2fps more. It is worth noting that the GPU will try to finish each frame as fast as possible even if you are CPU/monitor bound and this can result in the voltage and power consumption being needlessly high.

To cap the voltage just flatten the curve and this will limit how high the voltage can go.
capped.png

Here the voltage will not go above 832 mv.

What you probably want to do is to save 3 to 5 msi afterburner profiles that uses different voltage-caps, you can switch between these profiles depending on what games you play. When you want the best performance you select that profile.

https://youtu.be/xymefjRSNvI?t=314
 

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Memory overclocking
This is much easier than optimizing a voltage-curve. All you need to do is to increase the memory frequency until you run into stability issues.

With the 3090 you should be able to increase the memory frequency by around 1100 (in msi afterburner) beating the stock 3090ti.

If the memory becomes unstable it will typically manifest itself via artefacts on the screen rather than the game crashing outright (unless it's a highly unstable memory overclock).

A tuned 3090 should perform similar to a 3090ti (+11%) when using a 375W power-limit. You end up having paid less for a GPU that draws less power while delivering similar performance.

 

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Why you want to maximize the power-limit
Unfortunatily 30-series cards doesn't have that big of a voltage-span the cards can operate in. Minimum will be around 0.712v and if the load is too high the card will decrease it's clock without lowering the voltage at all.

The higher power-limit you use the less likely the frequency will be to drop below your minimum frequency you have set in msi afterburner. This is especially important when you have optimized the voltage-curve since then a lot more power will be limited to prevent throttling without efficiency gain.

30 series cards are not actually made to be fully utilized, you would need over 500W for that at the minimum voltage (in furmark). With typical usage only a part of the GPU will be used while most of transistors doesn't actually do anything, since this is the norm nvidia GPUs are made so big you cannot utilize the entire chip simultaneously well. This seems bad and it sortoff is but when you maximize the power-limit you will be very unlikely to run into this problem, instead the card will boost the voltage and frequency due to the thermal headroom (up to the maximum voltage or power-limit).
 
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