The Difference Is INSANE – Legion 7i Power Plan Testing

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It’s time for a bit of a different video, something that we have actually been wanting to look into for a while. The whole team has been getting deeper and deeper into notebook content lately, and as we are testing them one question keeps coming up in the comments: Exactly how much of an overall effect do built-in performance plans have on a gaming laptop? What is the best built an option for elements like battery life, gaming performance, noise, or simply a balance of all of those factors? I personally think that it’s a very important topic and it might change the way we look at gaming laptops in the future.
Custom OEM Performance Profiles
Nearly every one of today’s gaming laptops have built-in controls that go above and beyond what Windows offers. It’s actually pretty rare to see one using only the Windows power plans these days, and in many cases they straight up replace the standard options. The reason for this is pretty simple, people who spend big bucks on these notebooks want them to be a Jack Of All Trades that can be used for hours on battery, but at the same time also offer the highest performance when it’s time to game. The intent of this article is to offer you a snapshot of what these different power plans can achieve, and for that I have to thank Lenovo Legion for partnering with us and sending what is literally their most powerful gaming laptop.
Lenovo Legion 7i
This is the Legion 7i, and it is a beast. It’s fully kitted out with everything you could want in a gaming laptop. There is an Intel Comet Lake Core i9-10980HK CPU, an RTX 2080 Super Max-Q graphics card, 32GB of RAM, a couple of 1TB NVMe SSDs in RAID, and the option to configure the operating system with either Windows 10 Home or Windows 10 Pro. All of this fits inside a pretty slim 15-inch chassis. And if you want to check out a review of the 7i you can do that right here, but spoiler alert this is easily the fastest gaming notebook that we have ever tested.
Right now the 7i can be configured in a ton of ways, starting at $1,400 USD all the way up to this $3,000 USD monster. There is also the 5i series that offers a bit more affordable 15-inch and 17-inch options with Intel CPUs. I also need to give some credit to Legion for launching the new 5 series, that is a whole range of gaming notebooks with AMD’s awesome new Ryzen mobile processors. Expect a review on one of those very soon.
Legion’s Performance Profiles
Just like the competition, Legion offers 3 distinct and very straightforward power plans that override the Windows presets. The first one being Silent Mode, which limits fan speeds and performance, but at the same time is supposed to extend battery life, which will be much easier to live with. Then there is Auto Mode, which is the default power setting, and it’s supposed to balance out performance, heat, noise levels, and battery life. And then finally there is the Performance Mode, just cranks everything up to get the best possible performance out of this machine.
Switching between these can be done in one of two ways, pressing the Fn and Q keys on the keyboard will give you the option to quickly cycle through the modes with a quick indicator graphic on the screen. The benefit of this is that it can be done without ALT+TAB’ing out of an app. You can also go into Legion Vantage software and change things up there as well. As a visual indicator the power button also changes colour depending on which mode you are currently in. There is a blue for Silent, a light teal for Auto, and then red for Performance. There is also the option to switch things up in the Legion bios, and the option to engage an overclocking profile, but unfortunately our 7i sample didn’t have one loaded.
CPU Behaviour & CPU Performance
Now it’s time to overwhelm you all with results, but I also have to put them in perspective. The Core i9-10980HK in this system has a base frequency of 2.4GHz and a maximum frequency of 5.3GHz. That 5.3GHz can only be hit if Intel Thermal Velocity Boost algorithm detects that the CPU is operating at 65°C or lower. If it is operating between 65°C to 85°C, the maximum boost would be 5.1GHz. Starting off with temperatures in AutoDesk Maya, and in every mode the CPU initially hits above 90°C, but then the behaviors are really different. High Performance Mode sticks to 94°C for a good 30 seconds before settling down to about 82°C, while Balanced Mode keeps that higher temperature for 15 seconds, and then barely hits an average of 77°C. In silent mode you get about 15 seconds of slightly increased heat, and then like the others it falls, but in this case to just 56°C. Honestly, that’s the idle temperature of some recent notebooks we have come across.
What does that mean for clock speeds? Well those short bursts of heat at the very beginning directly align with higher frequencies. They boost for a short period of time and then level out. This is pretty normal for Intel CPUs, but it also tends to inflate results, especially in benchmark programs that have short run times. The i9-10980HK ends up at a constant 3.7GHz and 3.3GHz for Performance and Auto modes. Silent mode on the other hand doesn’t even allow the CPU to hit its base frequency.
Before switching over to power consumption, I do need to give you a little bit more context. The Core i9-10980HK has a nominal TDP of 45W, but notebook manufacturers can configure it up to a TDP of 65W. For all intents and purposes, the TDP in this case is basically the package power of the CPU. However, there is more to that. You see within those TDP specs are some power limits or PL subcategories that you will need to know about. I will try to explain it in easier terms. After a period of idle, we load the CPU and Power Level 2 gets implemented. PL2 is power that can be sustained only for a short period of time. In the i9-10980HK case that is up to a huge 135W, but it can only be configured down to 107W by a notebook manufacturer. Meanwhile, the Tau is the maximum length of the time PL2 to can be sustained for. In this CPUs case it’s 56 seconds. Finally, there is PL1, which is the long-term sustained power consumption, and that brings us back to the 45W to 65W TDP spec Intel gives us in their official documents.
All right, so let’s check out how the Legion is handling this. Initially, both Performance and Balanced modes allow the Core i9 to consume over a 100W for a short burst in the PL2 power state. The amount of time spent here directly aligns with the higher frequencies we saw in the last charts. Balanced then gradually makes its way down to a constant 60W, but in Performance Mode it looks like Legion might be implementing a higher than spec TDP since their cooling system can handle the increased heat. In Silent Mode it looks like the 7i can actually undervolt its CPU, so even when it’s under constant all-core load it only consumes 25W. That is a huge deal if you are on battery, but you still need to get some intensive work done.
One of the real benefits of these modes is how they affect noise levels. Silent Mode is literally whisper quiet, while Performance Mode spins the fans at almost maximum speed so those higher frequencies can be maintained. Meanwhile, Balanced Mode is a nice, happy medium between the two and believe it or not in that setting the 7i is actually one of the quietest notebooks that we have come across.
What does this all mean for performance? Well between Balanced and Performance the numbers are really, really close, so much so that unless you really need that extra speed I would actually recommend you keep this notebook in Balanced Mode. If you decide to run it in Quiet Mode, it completely handicaps performance in most cases. However, in Adobe Premiere Pro there is literally no difference between the three. While all the other tests load the CPU at maximum, Premiere actually balances loads between the CPU, the integrated graphics, and the discrete graphics card. As a result, none of them are working at full capacity or even close to their power limits, and even Quiet Mode can maximize performance, which is actually pretty cool.
Now what really shocked me was how little of an impact the modes had on battery life when browsing the web or doing simple tasks like spreadsheets or word processing. That is because every one of them allowed the Core i9 CPU to enter its lowest near idle power state. However, once you start loading up that CPU with more intensive tasks, there is an epic difference between the modes. The Silent Mode gets nearly four times the battery life of the Performance Mode. The only limitation with it is processing intensive tasks will take much longer to finish.
GPU Behaviour & Gaming Performance
Moving on to gaming, and if you thought the last results were interesting hold onto your hats cause this one is pretty wild. When we analyze CPU frequencies over time for Auto and Quiet modes they are pretty close to one another, but check out the High Performance mode. While the other two dip after a few seconds, this thing just keeps going on and on at 4.4GHz. Analyzing CPU temperatures over time, here we are seeing a lot higher temperatures since there is some additional heat being built up by the GPU that gets transferred to the i9-10980HK. After testing a ton of notebooks we have come to expect this kind of behavior when gaming. Now since gaming doesn’t require a 100% load across the CPU cores, all the performance modes are able to operate at much lower TDP levels than in our AutoDesk Maya test. What I really want to point out here is the law of diminishing returns when it comes to CPU speeds versus power. The Silent and Auto modes only need between 25W to 30W to hit about 3.5GHz, meanwhile Performance Mode requires double the power for about 25% higher frequencies.
Moving onto the GPU, and this one had me scratching my head for a little bit. Even though Performance Mode allows the CPU to operate at really high clock speeds, and its initial GPUs speeds are better here, Auto Mode actually allows for slightly higher average frequencies as time goes on. The difference between all three modes is only about 60MHz, so even though the chart scale might make the gap look quite big it actually isn’t. Another thing to note here is that NVIDIA rates the RTX 2080 Super Max-Q at between 1080Mhz and 1560MHz, so these are all at the higher end of that spectrum. The odd thing is that Auto pushes the RTX 2080 Super to reach temperature levels that are a good 5°C hotter than the other two modes. Based on all the other tests, I would have expected High Performance Mode to take the crown here, but that wasn’t the case. The plot thickens when you start taking a look at power consumption, you see after a few minutes the Auto Mode is really allowing the GPU to stretch its legs a bit more at 95W of constant power consumption. High Performance isn’t too far behind at 90W, while Silent Mode hits NVIDIA’s 80W spec. What is probably going on here is lower fan speeds are driving up temperatures and the increased heat also leads to more power being used. We were all wondering why High Performance didn’t get higher GPU clocks, but I think in that mode the Legion 7i still puts emphasis on the CPU’s performance rather than giving more thermal and power budget to the GPU.
Looking at the actual gaming results, there really isn’t that much difference between High Performance and Balanced mode on average, but – and this is a big but – the increased CPU frequencies seems to really improve the 1% lows and overall smoothness of gameplay. As for the Quiet Mode, well that still delivers really respectable frame rates, but the combination of lower speeds for both the processor and graphics cards combine to lower performance by a noticeable amount. The acoustic levels when gaming are basically in-line with what we expected, so basically a bit higher than when the 7i is being hit with an all-core CPU load.
Conclusion
Honestly, I think that these tests really opened our eyes in a few ways. It’s really interesting to see how companies like Legion are taking their gaming notebooks and packing them with different performance modes that actually make a difference. Simply flipping a switch can turn a noisy, hot, high-performance gaming notebook into one that is silent and offers longer battery life when you need it. Now do I think that the extra noise and heat level of Performance Mode is worth it over Auto? Not necessarily, because it feels like a diminishing rate of return. However, it is really nice to have that extra shot of adrenaline when you absolutely need it.
Most importantly, all this testing also shows that we might need to add a bit of extra testing to future notebook reviews in order to show a realistic view of performance in more situations. And yes, that is more work for us, but while testing at the highest performance mode shows the best possible case, it might not be the right setting for everyone. What performance mode do you guys run your gaming laptops when they are plugged in? Is it the highest performance setting or do you choose balanced or do you switch between the two depending on your use case scenario? I’m curious to know.