Tips for selecting RAM in 2018

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Derek Semeraro
Posts: 124
Joined: Sat Sep 23, 2017 6:49 am

Tips for selecting RAM in 2018

Post by Derek Semeraro » Thu Mar 22, 2018 8:17 pm

While not directly related to silence, it is a decision builders (and buyers) will make, especially within the context of the CPU and motherboard they choose, so I wanted to give tips for beginners, or those who haven't built a PC in several years:

CPU choice
All RAM does is allow your computer to run as fast as your CPU can run. RAM doesn't inherently make the computer faster. It only removes the blockage that's hindering your CPU. If you buy a great CPU and an unideal amount of RAM, you can always add more RAM. However, no amount of additional RAM can make a bad or very outdated CPU good.

Motherboard choice
While ATX and EATX boards allow for 4-8 sticks of RAM, ITX and many Micro ATX boards limit you to two sticks of RAM (which probably isn't a big issue for most builders). If you have a motherboard with two slots, it's better to go with one larger capacity stick than two smaller ones since you can always upgrade the second slot later. Also, the DDR of your RAM must be the same as the DDR your motherboard accepts - there is no backward compatibility (DDR4 motherboards must have DDR4 RAM).

RAM speed
CPU's and motherboards will have, in their specs, the amount of RAM speed they can tolerate. Of course, many motherboards allow you to overclock the RAM in the BIOS to get higher speed. Additional RAM speed can improve performance, depending on the how the CPU utilizes it, of course. There is a little bit of improvement in performance when moving along the 2400-3000 MHz range, but beyond that there are very diminished returns. If you use two sticks of different speeds, it will run at the speed of the slowest stick.

RAM power consumption
Each stick of DDR4 RAM consumes a negligible amount of energy (1-2 watts?). Cooling, noise and wattage isn't a meaningful concern for RAM.

Symmetry
While this aspect is not mandatory, and may not be necessary for everyone, it is generally more reliable to have sticks be of the same size, same brand/model and when using more than one stick, it's best to have an even number of sticks.

RAM capacity
If using a light OS like Linux, 2-4 GB should be fine. For Windows or Mac, 8 GB is recommended for most users. 8 GB is plenty for the vast majority of productivity, web browsing and office programs. For modern computer games, 8 GB is plenty (16 will have little to no improvement on games). For creative work, such as Photoshop, Adobe Premiere, Digital Audio Workstations and 3D modeling, more RAM is recommended because many of these programs are designed to use as much RAM as possible. More RAM will yield faster workflow. For those using apps like these as a passion or a profession, it may be a good idea to start with 16 GB (and then see if you need more). If you can only afford 8 GB of RAM at the moment, these programs are still very viable, those that are passionate about what they create will still be able to create great things and this shouldn't discourage any creative minds from pursuing these programs. In a few years, 16 GB may be more beneficial for many, but with many websites and apps being designed for mobile and budget markets, I expect 8 GB to not become obsolete for most users anytime soon.

RAM price
Right now, RAM is at an all-time high price. When it was cheap, buying extra wasn't a bad idea, but now additional RAM comes at a higher opportunity cost of dollars that could be invested into other parts of the build. I generally tell people to buy as much RAM as they need at the moment and don't try to future proof. If the programs you use don't even need the extra RAM, you may be spending an extra $80-160 for nothing.

zdb
Posts: 18
Joined: Sun Jan 28, 2018 11:59 am
Location: Australia

Re: Tips for selecting RAM in 2018

Post by zdb » Tue Apr 17, 2018 12:24 am

All things considered, a good guide. I do have a few points to make, though:
Derek Semeraro wrote:If you have a motherboard with two slots, it's better to go with one larger capacity stick than two smaller ones since you can always upgrade the second slot later.
If money is tight and performance is less important, then that is a viable strategy. If, however, your two-slot motherboard is dual-channel (and most of them are) and you only stick in a single DIMM — make use of a single channel — then you can expect memory performance to drop as much as 45%... and that makes a huge difference in many types of use cases (e.g. gaming). Two smaller-capacity DIMMs far outperform one larger-capacity DIMM on two-slot motherboards with dual-channel memory architectures.
many motherboards allow you to overclock the RAM in the BIOS to get higher speed. Additional RAM speed can improve performance, depending on the how the CPU utilizes it, of course. There is a little bit of improvement in performance when moving along the 2400-3000 MHz range, but beyond that there are very diminished returns.
Folks looking at getting something like an AMD APU (e.g. Ryzen 2200G, 2400G) need to be aware that — on systems where CPU and GPU are integrated and share the same RAM — RAM speed has a huge impact on graphics performance. AMD's Infinity Fabric scales according to RAM speed... so if you want to use such processors for graphics-intensive tasks (e.g. gaming) then fast and overclocked memory is the easiest/best way to increase your FPS. Consider 3200MHz RAM to be the absolute minimum on such systems.
If using a light OS like Linux, 2-4 GB should be fine. For Windows or Mac, 8 GB is recommended for most users. 8 GB is plenty for the vast majority of productivity, web browsing and office programs.
I'm running Ubuntu 16.04 right now, only have a web browser and mail client open, and I'm using 3.9GB of RAM. The OS is less important than the applications you use. Web browsers, in particular, can consume vast amounts of memory — and you use them regardless of the underlying OS. Unless your needs are clearly known and minimal, I wouldn't even think of building a general-purpose computer with less than 8GB of RAM in it nowadays.

Another thing to keep in mind is that if you install an insufficient amount of RAM, and you use it up by <doing stuff>, then your OS will use your SSD/HDD as a swap device to avoid crashing. Not only will this reduce the performance of your machine but it will also cause additional wear and tear on your SSD/HDD. In other words, if you don't install enough RAM in your computer it will run slower and you'll corrupt/kill the SSD/HDD faster. I think that's a false economy. My advice is not to go below 8GB unless you know what you are doing.
Right now, RAM is at an all-time high price.
Yep, but unfortunately the new fabs won't come online until the second half of 2018, which is why RAM prices will likely rise a little bit more through the middle of the year, flatten out in the second half of 2018, then — hopefully — slowly start falling in 2019 as supplies increase. (GN did a good report on RAM prices earlier this year.) So, the prices we have now in 2018-04 are likely to be very similar to the prices we'll see in 2019-04 — meaning that you'll have to wait at least a year to have any realistic chance of saving even a small amount on RAM. If you can afford to wait at least a year, then go for it. If you need your RAM within the next 12 months, however, then you are better off buying it right now.
Last edited by zdb on Wed Apr 25, 2018 2:34 pm, edited 1 time in total.

Derek Semeraro
Posts: 124
Joined: Sat Sep 23, 2017 6:49 am

Re: Tips for selecting RAM in 2018

Post by Derek Semeraro » Wed Apr 25, 2018 6:35 am

Yes, I agree with all of your points. Dual-channel is generally better for performance. RAM prices will eventually ease, but probably not anytime soon this year; the best solution is to buy as much as needed right now and not buy enough RAM for the next several years.

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