Undervolting my new GPU

I finally got a GPU around 2 months ago after waiting over a year. GPU shortages are insane right now and have no end in sight.

While I could have bought a GPU far sooner, I refuse to give scalpers money and I also refuse to spend 4+ hours a day trying to get one. So I just took it slow and signed up for Stock Drops and when I was around during the alerts, would occassionally give it a try. At first I was trying every time i got the alerts, but even checking within 5 seconds of the alert it would always be sold out, so I kind of gave up.

Recently I got an alert for a Nvidia 3090 founders edition at BestBuy (the ideal place to get it as you can get them for MSRP) and clicked the alert within about 1 second of getting it and was able to add one to my cart. Within a week or so I had the card and installed it.

I haven't really done much to overclock or undervolt the card, as this usually takes time and testing and I just wanted to get back to working and playing games without the hassle.

I primarily only play Hunt: Showdown, most of the games I want to play and the old games I never got around to finishing or playing I just put on hold until I got a good GPU and time enough to play.

I recently upgraded to an UltraWide 1440P monitor and before the new GPU it put Hunt: Showdown below ideal frame rates. Prior to the monitor, I was getting around 70-80 FPS, not enough to max my 144 Hz monitor, but certainly very acceptable. After the monitor, I was in the 45-60 FPS with ocassional dips even lower. This was a noticeable issue during big fights and proved to be a disappointing experience. In most cases it would have been acceptable but Hunt is a very high skill cap came with very quick reaction times.

Luckily, I got my GPU not too long after and was able to improve my FPS to more than acceptable levels. After installing the 3090 I was looking at around 120-144 FPS in Hunt with all settings maxed out. Previously I was able to max all settings but lighting, I had to turn lightning to the lowest setting as it had a massive impact on the frame rate. Shame because it looked so good with maxed lightning.

Fast forward to today, and all is good. I'm getting fantastic frame rates with full UltraWide experience. I do want to optimize the performance of my GPU though, especially since I will start using it to mine Ethereum when not using it.

In the past, overclocking was the go to thing to do. Now days, undervolting is the more popular option. When you overclock, you can usually get 5-15% more performance out of your GPU for a singificant power increase. In the past most wouldn't even pay attention to power usage unless they were mining.

Now days GPUs are using upwards are 400W alone and power is a big concern. The 3090 is especially power hungry coming in at around 350W+ stock.

I did some quick testing using the UniEngine Heaven benchmark. This is an older benchmark and not as demanding as others, it also doesn't test things like Ray Tracing, but I honestly don't care much as it is still going to give me a good relative comparison between stock and undervolted. I don't want to spend too much time on this, I just primarily want to get 80% of the benefit with 20% of the work.

Using stock settings, I was able to get a max of 394.5 FPS with a min of around 106.6 FPS. Temperature was around 61 C at the end of the test. Watching GPU-Z on my other monitor, I was seeing 345-352W total usage on the GPU.

I then started to undervolt the GPU, I am going to use a known good starting point to see how it goes. I'm not going to spend a lot of time tweaking it, I really just want 80% of the benefit with 20% of the effort.

The first thing I do is reduce the core clocks 200 MHz.

The reason for this is to reduce all clocks to below the threshold I am going to set for the power curve. I am going to target the popular 1850 Mhz @ 0.850V. Stock is 1900 Mhz @ 1V.

First I target 1850 Mhz @ 0.850 in my power curve editor.

Then I hit apply to build a curve around this target. As you can see the curve now caps at 1850 Mhz with 0.850V target. I will end up with 50 Mhz less clock with a significantly lower power usage.

The final result ended up with significant lower power usage and better overall performance. Although the difference in performance is extremely minor, the power reduction was not.

As you can see here we went from 61C at the end of the benchmark's first five stages to 54C with the undervolting. Max and min framerates went up a little in the process as well.

This is a pretty significant improvement without any loss in performance. In fact, performance is a tiny bit faster than before.

Another more aggressive curve is targeting 2000 MHz @ 0.987V.

Here I noticed very similar results as the 1850 MHz overclock with more wattage used. This is likely the result of the benchmark not really stressing the GPU enough to take advantage of these settings. I noticed the GPU rarely went above 1850 Mhz. Using a more modern benchmarking software would have allowed me to stretch the legs a little more and got a more accurate result.

I am happy with the results though, slightly less power usage for similar performance. I will spend more time later optimizing it better, I just wanted some improvements without putting a lot of effort in.

I decided to stick with 1850 Mhz @ 0.850V which is great for mining and still gives me 100% of the performance while gaming.

Posted with STEMGeeks