End of Year PC Build

When you manually overclock, you lock all the cores at a specific speed. The key here is to find the right voltage so you get a stable overclock at that speed.

Undervolting makes more sense when it's applied to CPU boost and not manual overclock. Modern CPU cores are designed to boost as long and as much as the thermal limit and power limit allow to. So when you have a very beefy cooling solution like a custom water loop, you can really take advantage of the extra processing power because now your CPU has a lot more thermal headroom to play with. Basically, just think of boost = dynamic auto overclock. Intel calls it Turbo Boost and AMD calls it Precision Boost.

However, if you have smaller cooler such as in a laptop or small-form factor build, your CPU hits that thermal ceiling a lot sooner and also a lot more often. That means more thermal throttles. This is where undervolting can help you get that little bit of extra performance and more importantly, make it a lot more power efficient as well. By undervolting, you're essentially reducing the energy consumption of the CPU and also reducing heat without affecting the performance. When you manually overclock a CPU, you try to find the minimum voltage for a stable overclock. Similarly when you undervolt a CPU, you are finding the lowest voltage offset where your system remains 100% stable. Lower voltage means lower temperatures. Lower temperatures means more thermal headroom, and more thermal headroom means more performance through CPU boost.

AMD's Precision Boost Overdrive takes the CPU boost algorithm to another level by increasing the system power budget beyond the stock specifications. Like CPU boost, it takes all the SoC info such as current, voltage, and temperature through an algorithm and dynamically adjusts the SoC power and VRM current on the fly. Keep in mind that it doesn't actually increase the boost clock speed but the extra power headroom allows more cores to have the opportunity to boost to that limit. (You may set it to go over the stock boost clock, but I believe it only allows a mere 200mhz overclock.)

For Zen 3 Ryzen CPUs like the desktop Ryzen 5000 series, AMD has another tool called the Curve Optimizer for Precision Boost Overdrive. The Curve Optimizer is basically adaptive undervolting. So rather than applying a fixed reduced voltage offset across the whole low load and high load scenarios, Curve Optimizer takes in all the system information details such as workload, temperature, socket power availability, and puts them through an algorithm. It then calculates how much voltage can be reduced and it is done in a matter of one millisecond. That means it can do that 1000 times in a second.

For a Ryzen 5000 CPU, Precision Boost Overdrive + undervolting through the Curve Optimizer is pretty much the easiest and the most efficient way to overclock. It is pretty much unbeatable.

Also you shouldn't get any stutters from AMD's Precision Boost. If you do, there's something else wrong with your PC.

If you really want the Logitech Z633, you should just get them already. They're only like $90-$100 USD.

However, getting new speakers or a new sound card probably won't magically fix your low dialogue volume issues. That's something that you have to tinker with the Windows speakers setup tool and the movie playback app that you use to downmix 5.1 channels into stereo.

For example, I still use CCCP for video playback. LAV handles all the audio decoding in CCCP and it also handles all the audio mixings including 5.1 to stereo downmixing.

I can simply turn up the center mix channel to increase the dialogue volume with LAV. If you use a different video playback app, you just need to figure that out yourself.

If none of these fixes works, you may try normalizing the sound volume. Windows 10 also has a built-in loudness equalization tool that you can use.

If you don't see that option, you can probably find it in your sound card/onboard audio software. They usually have custom tools that can tackle these issues.
For my Sound Blaster AE-7, it has something called "Dialog+" to boost the dialogue volume and "Smart Vol" to normalize sound volume.

So buy the speakers because it seems like you really want them. As for the sound card, I say save your money unless you're 100% sure that it can fix the low dialogue volume issues.

It should always be the first step to bump up the db before using the latter program video.

His main problem is that he can't hear the dialogues in movies too well. So I'd try to boost the center channel first or normalize the entire sound volume. That way you don't get very quiet dialogues and very loud action scenes that can blow out your eardrums. That's why this should be the priority.

Once the audio has been normalized and he can hear the dialogues more clearly, then he can work on boosting the entire audio channels or just simply turn up the volume.