card in your laptop is worth it. We’ll perform some gaming benchmarks with and without a

second graphics card in use and find out how much extra performance Nvidia’s SLI actually

gives us in various games.

Nvidia allows us to run multiple graphics cards together in order to get better performance.

This is known as SLI, and is available in laptops. While this sounds great, SLI has

some drawbacks. SLI is not perfectly scalable, for instance if you get 50 FPS in your favourite

game adding a second GPU will not increase you up to 100 FPS. The real result will depend

on many factors, including how well the game developers implemented multi GPU support.

Not only do you have to pay more for a second graphics card which physically requires more

space in your laptop, an additional card will increase power usage and heat output, as well

as create extra noise due to the extra cooling. Not only will the additional graphics card

also add additional weight to the laptop, but the additional cooling will also add more

weight too. These various aspects need to be carefully considered in a laptop environment,

as you only have as much power as the battery installed unless you’re always plugged in.

In order to determine if the extra performance is actually worth it, I’ll perform some

benchmarks so we can get an idea of how the laptop performs with a single graphics card

and with two in SLI. This particular laptop has dual Nvidia 1070s installed, and I’ve

done a full review on it previously if you’re interested. We’ll start with some real world

gaming benchmarks and then move onto synthetic benchmark tools. The laptop also has an Intel

7700K desktop CPU, I’ve overclocked it to 4.9GHz in order to help reduce the CPU as

a potential limiting factor as much as I possibly could. For reference I’ve also included

the non overclocked results as well, however I didn’t actually record the CPU maxing

out at all during any of the tests anyway. Additionally I didn’t experience any thermal

throttling throughout any of my testing.

In GTA 5 I’ve disabled VSync and tested with FXAA on with MSAA set to x8 with a 1080p

resolution. With SLI disabled we averaged 75 FPS, and with the CPU overclocked this

remained the same. With SLI enabled, we averaged 86 FPS, and with the CPU overclocked the average

increased to 101 FPS.

In the Witcher 3 I used the Ultra preset, disabled VSync and NVIDIA Hairworks, and again

ran at the full 1080p resolution. With these settings and with SLI disabled we averaged

78 FPS, and with the CPU overclocked this actually dropped slightly to 77 FPS. With

SLI enabled, I was able to get an average of 108 FPS, and with the CPU overclocked this

increased a little to 115 FPS.

In Shadow of Mordor with ultra settings at 1080p a single 1070 averaged 151 FPS, and

150 FPS with the CPU overclocked. With SLI enabled we averaged 169 FPS, and this result

did not change with the CPU overclocked.

From these tests it appears that the difference with and without CPU overclocking with a single

graphics card is basically the same, the differences are within the margin of error, however it

does appear to make more of a noticeable difference with SLI enabled. I suspect that because with

more graphics power available the faster CPU may be of more use. It will also depend on

other variables such as how much does the particular game rely on the CPU.

In my opinion these real world gaming benchmark tests that I’ve covered so far are what

you should mostly consider, as they show how much practical difference you would actually

expect with and without SLI. The synthetic benchmarking tools that I’ll be using next

aren’t as useful as a practical indicator. In real games adding a second graphics card

doesn’t scale perfectly, whereas in these tests they are designed to perform very well

with additional resources, making it appear that SLI is a larger boost than it really

is, so take them with grain of salt.

In Heaven benchmark with the quality set to ultra, tessellation set to extreme, and anti-aliasing

set to x8 at 1080p, a single 1070 averaged 91 FPS and 92 FPS with the CPU overclocked.

With SLI enabled, the 1070s averaged 152 FPS, and with the CPU overclocked this increased

to 161 FPS.

In Valley benchmark, with the quality set to ultra and anti-aliasing on x8 at 1080p,

a single 1070 averaged 90 FPS and this stayed the same even with the CPU overclocked. With

SLI enabled, both 1070s managed to average 112 FPS. With the CPU overclocked this increased

to 123 FPS.

Next I ran the both the Fire Strike and Time Spy benchmarks from 3DMark, and in Fire Strike

got a score of 14,546 with a single 1070, and a score of 21,207 with SLI enabled. With

the CPU overclocked, I got a score of 14,590 with a single 1070, and a score of 22,147

with SLI enabled.

As for Time Spy, I got a score of 5,384 with a single 1070, and a score of 9,082 with SLI

enabled. With the CPU overclocked the single card score increased to 5,394, while the score

with SLI enabled rose slightly to 9,129.

Based on my results, without performing any CPU overclocking on average having a second

1070 in SLI improved the average frame rate of the games tested by 17.2%, while the synthetic

benchmarks saw an improvement of approximately 33%. With both types of results combined,

we saw a 26.2% improvement on average over all tests with SLI enabled.

Overclocking the CPU did not appear to change things with a single 1070 in use, however

as we have seen with SLI enabled we did actually see a small boost in all results. With the

7700K overclocked to 4.9GHz we saw an average improvement with SLI enabled of 23.3% in the

games tested, and an improvement of 36.2% in the synthetic tests. With these results

combined together we saw an overall improvement of 30.7% with SLI while the CPU was overclocked.

After considering the results of these tests, I find it difficult to recommend getting a

laptop with SLI unless you really want the extra small increase in gaming performance.

You may get a better bang for your buck by simply getting a better single graphics card,

for example while this laptop has two 1070s it also has the option of a single 1080 which

is cheaper, and may perform better in various games, I can’t say for sure as I’ve not

personally tested a 1080 yet. In general getting a better graphics card instead of SLI is a

better choice, with SLI you’re relying on the game developers implementing multi GPU

support in an efficient manner which will vary based on the game, essentially the additional

card just doesn’t scale that well for me to think it’s worth spending hundreds of

dollars on.

If the extra weight, heat, noise, and cost aren’t an issue and you’re still interested,

then by all means go for it, however if these other factors matter to you then you may need

to think twice before buying an SLI based laptop. If you’re getting a laptop with

SLI also make sure that you pair it with a display capable of a higher refresh rate,

a standard 60Hz panel for instance is probably not a good idea if you actually want to be

able to take advantage of those higher frame rates that you’re paying for.

So what do you guys think about getting SLI in a laptop? Is it something you’d consider

paying more for to get the extra performance, or would you just get a more powerful single

card? Be sure to let me know your thoughts down in the comments, and leave a like on

the video if you found it useful. Thanks for watching, and don’t forget to subscribe

for future tech videos like this one.