This is a bit of a tough question to answer, if only because these two different types of memory offer different kinds of benefits and advantages and they aren’t really a true “apples to apples” kind of comparison but much more of an “apples to oranges” one.
Yes, the overwhelming majority of “regular” computer user are definitely going to be able to take advantage of the 16 GB of DDR3 memory more so than not – but there are some unique instances where it may be more advantageous to have just 8 GB of DDR4 memory in your computer, depending upon the kind of hardware that you’re running as well as the programs and software that you have taking advantage of the available memory to begin with.
Brian, IT Support guy from Auckland (New Zealand) says “As a general rule, DDR4 is significantly improved in the power savings department, but even there the advantages aren’t all that noticeable to your every day average user.” The latency of this kind of memory is definitely higher than DDR3 memory, even though the RAM is clocked at higher speeds.
So there aren’t going to be any immediate performance bumps when it comes to using the 16 GB of DDR3 versus the 8 GB of DDR4 – unless of course you’re using pretty resource hungry programs and applications as well as hardware options that need more base memory.
You see, if you’re running multiple applications and pieces of hardware that are drawing more than 8 GB of available memory your programs are going to start paging – and that’s when your speed is going to slow down considerably.
Your computer will slow down to almost a crawl as it fights for every scrap of available memory, and it will put quite a bit of pressure on top of your available RAM in a way that you probably wouldn’t have expected or anticipated. The 16 GB of DDR3 memory in that specific situation would help make your computer significantly faster, if only because it makes more memory available to your computer and to your programs so that this kind of paging doesn’t happen in the first place.
At the end of the day, DDR4 memory is the next iteration of RAM and has some benefits over DDR3 for sure. But if you are going to be using really resource intensive programs and hardware that is heavy on your RAM allocation, it may be more advantageous to go to the previous generation of DDR3 and get your hands on 16 GB versus half that of the new stuff.