I disagree with the other user that you HAVE to get DDR5. You probably don’t. It really depends on what you want your computer to do and your budget. But it is true that to upgrade your CPU you will probably have to upgrade your motherboard and likely your PSU. If you’ve ever been riding the line of hitting the max wattage on your power supply, you will need a new PSU. This is a problem that I ran into when I looked to upgrade my computer because modern CPUs tend to have a lot of power-suck potential.

The real question you should be asking is why you want to upgrade and what you’re going to use that upgrade for. After that, you can start looking at your budget and trying to figure out what you’re going to buy. If you want to stick with older generations or sockets like you have, you’re also going to have to keep in mind that you’ll likely be buying used as almost no one keeps new old stock of these things. That comes with a sharp drop in price, which is great especially since it often provides the best dollar-to-power ratio. But it comes with drawbacks like the risk of faulty parts and no warranty.

If you insist on sticking with the LGA-1151 motherboard that you have, do know its limitations in excess of which CPUs are compatible with it. It can’t run DD5, but you probably don’t need it to. DDR5 is still pretty young and pretty expensive. Its raw clock speed is impressive, but you’re going to be getting worse timings unless you make some sacrifices. And a lot of users won’t be taking advantage of that extra speed anyway. Do know if it can handle M.2 chips because if you ever want to upgrade storage, they’re getting to be the best deals around with SATA SSDs often having similar longevity, similar capacity, and sometimes even similar prices, but far lower speeds. And hard drives are becoming less and less reasonable unless you NEED a lot of relatively cheap, slow storage right now like for a NAS. Even then, SSD NAS setups are becoming more reasonable and already are more reliable. That isn’t important to everyone, but it’s something to keep in mind.

If you want to stick with your LGA-1151, I’m not sure which revision your board/socket is, you can look that up, but that means you’re dealing with your same sixth-generation CPU’s siblings or their seventh-generation cousins. It’s possible that your board might support eighth-generation, but I doubt it as the socket went through a minor revision, and the new one often only supported eighth-generation. This really limits your ability to upgrade. It’s likely that if your budget is tight you’ll want to upgrade to 10th- or 11th-generation CPUs if you’re sticking with Intel or look at some AMD CPUs and see what your options are in your budget range. You might even be able to get a 12th-generation build done for a reasonable price. I recently did a 13th-generation build for myself and kind of regret it. The price-to-performance difference between 12 and 13 is not great and the most recent components have been seeing a higher failure rate, possibly due to changes brought on by the pandemic.

All this can get overwhelming, I know, I’ve been there. And it takes some time for all the information to start sinking in and making sense. But in truth, it all comes down to asking that initial question: Why do I want to upgrade? If you want to upgrade just to play games, well, firstly, what kind of games? Most games are not going to bottleneck at the CPU, even with one as old as yours, though there are some CPU-intensive titles and genres. If you want it to be a slightly better but not state-of-the-art workstation, what kind of work is it going to be doing? Programmers and accountants are going to want beefy CPUs to process lots of data (more and faster RAM isn’t a bad idea for either of them) whereas video editors and graphic designers are probably going to want mid-tier ones and spend the extra on a better GPU and RAM. And a million other use cases. It can be hard, especially if you’re just starting out, to actually answer these questions honestly. But I know from experience that if you don’t take the time to, you will end up with buyer’s regret. I won’t be able to answer a lot of your questions, but if you want to ask me anything more, feel free to.