Tag Archives: PC Building

About PC Memory

If you’d rather watch a video than read.

Layered Memory

Computer memory is a fairly complicated topic. The general principle is that you always have to compromise – choose one: price, size, access speed. So the sensible solution is combine different types of memory in several layers.

Layer 1 – Registers

The absolute fastest type of memory are registers, located directly in CPU Cores.

Any value that participates in CPU’s calculations eventually passes through registers. For example, if you were to ask your CPU to calculate 1 + 2, the CPU would put “1” in one register, “2” in second register, and then run the calculation and write the result in one of the registers.

Registers are super fast, but they are also super small. Basically, each register can store only one value.

Layer 2 – CPU Cache

CPU Cache is the link between CPU and RAM. Even though RAM is pretty fast, it still takes time to access. 

So whenever a CPU does take something from RAM, it copies a few neighboring blocks of information as well, as it’s highly likely they will be needed next, and puts them into CPU cache.

The next time a CPU needs to take something from RAM, first it will look in CPU Cache.

If Cache contains the information CPU needed, it’s called a Cache Hit.

If it’s not there, and CPU still needs to look in RAM, it’s called a Cache Miss, and effectively the CPU just wasted time. 

Larger cache makes cache hits more likely, but it also takes more time to sift through, so you have to strike a balance. If you make cache too large, it will take so long to search all of it, that it would be faster to just address RAM directly. 

You are already familiar with solution to this problem – CPU Cache is made of several layers, called levels. Each next level is larger and slower than the previous one.

When CPU needs a certain value, first it checks Level 1 cache. If it’s not there – Level 1 Cache Miss – it checks Level 2 Cache, and so on. Most modern CPUs have three cache levels. 

Different CPUs will have different amount of cache, and CPU description at various internet shops will often list Level 3 Cache size, as if it’s a value that’s supposed to mean anything to you. It’s really not. Unless you’re a CPU architecture engineer, you cannot judge a CPU by its cache size. You simply don’t have enough information. With some research, you can find cache size for every level, but there are tons of other questions. What is the access speed for each level? What is the projected cache hit rate? How does cache work in this specific CPU architecture? What are the effects of cache performance on the overall PC performance? It’s just way more trouble than it’s worth. 

So when choosing a CPU, don’t look at cache size at all. 

Layer 3 – RAM

RAM – stands for Random Access Memory – is a temporary storage for things that CPU is likely to need in the near future. RAM needs a constant supply of power to store information. If the PC is powered down, all information stored in RAM is lost.

RAM modules have a lot of differences:

Generation

Currently, DDR3 and DDR4 are the most common generations. 

DDR3 was released in 2007 and is slowly being phased out by DDR4. Standard voltage for DDR3 is 1.5V, overclocked modules go up to 1.65V. Standard operating frequencies go from 800 MHz to 2400 MHz.

DDR4 was released in 2014. Compared to the previous generation, it  works at higher frequencies while consuming less power. Standard voltage is 1.2V, overclocked modules go up to 1.35V. Standard frequencies lie somewhere in 2133 MHz to 3200 MHz range, but there are overclocked kits that go all the way to 4400 MHz.

DDR3 and DDR4 are not cross-compatible.

Form Factor

Full-sized DIMMs are intended for desktop computers, while smaller SO-DIMMs are commonly used in laptops. They are not cross-compatible.

Frequency

Frequency determines the RAM cycle rate. When the CPU requests some data from RAM, a certain amount of cycles will have to pass before the data download can start. That amount of cycles is defined by RAM’s timings, and frequency determines how long does it take for these cycles to pass.

Once the data download starts, 64 bits of data per channel will be downloaded each cycle. 

So RAM frequency determines both how fast data can be accessed, and how long it takes to download it. Higher frequency both makes RAM more responsive and increases throughput.

Timings

Timings determine RAM’s latency – how many cycles does it take to access certain data. Shorter timings will have a positive effect on RAM performance, but this effect is less noticeable than higher frequency.

There are four main timings, usually listed in RAM’s tech specs. For example, this Crucial RAM has 8 – 8 – 8 – 24 timings:

However, there are many secondary timings. When you have several RAM modules installed, all their timings must be exact same. That’s why it’s highly recommend to buy RAM modules only in kits, which are guaranteed to have all timings to be exact same. 

There is no such guarantee if you buy several same kits from the same manufacturer. That said, you can “make” them compatible if you’re willing to fiddle with secondary RAM timings in BIOS. You may have to first install kits separately from each other to find out which of their timings are different.

The important thing to understand is that timings’ effect on performance is directly tied to frequency. RAM with super short timings and low frequency can potentially yield better performance than RAM with higher frequency, but longer timings. And vice versa. 

Capacity

Most common capacity for one module is 2 GB, 4 GB, 8 GB and 16 GB. For best performance, you should always use modules with the same capacity. At the very least ensure that all channels have the same capacity.

Rank

Memory modules can have 1, 2, 4 or 8 ranks. Having a multi-ranked module is more or less the same as having several separate modules in one. In other words, you could install four single ranked modules, or two dual ranked modules, and as far as your computer is concerned, both cases would count as having four separate RAM modules.

Having multiple ranks in the system increases performance. Think of each RAM rank like an open book on your desk. The more books you have, the higher the chance that when you look at those books, at least one of them will be open on the page you need.

Some tests were performed, and with all else being equal, dual ranked RAM provided up to 13.5% boost to minimum FPS in Hitman compared to single ranked RAM.

However, there is a maximum amount of ranks that a system can support. Additionally, using multiple ranks can potentially force the RAM to work at lower frequency. For example, AsRock B350M Pro4:

As you can see, it supports highest frequency when the system has 2 ranks, lower frequency when there are 4 ranks in dual ranked modules, even lower frequency when there are 4 ranks in single ranked modules, and lowest frequencies when there are 6 or 8 ranks.

Keep in mind that ONE dual ranked module will not work in dual channel mode. 

You can combine RAM modules with a different amount of ranks within the same channel. For example, having a single ranked RAM module in A1 slot, and a double ranked module in A2 slot will work just fine. I wouldn’t recommend having different amounts of ranks in different channels, though.

Number of Channels

Depending on CPU’s memory controller, RAM can work in 1, 2, 3 or 4 channel mode. Dual channel is the most common one.

RAM can transfer 64 bits of data per channel. So in dual channel mode it will be able to transfer 128 bits of data. While this does double theoretical throughput, the actual effect on RAM performance is somewhere between 20% and 50%. 

It is still a sizable boost, and you should always go for dual channel. Keep in mind that on motherboards with more than 2 slots, it does make a difference in which slots RAM modules should be installed in order to be able to work in dual channel mode. Consult your motherboard’s manual for that, as shown on the picture.

RAM Compatibility

What kind of RAM can you use depends on:

Operating System – determines maximum RAM capacity.

Motherboard and CPU, which contains the memory controller – determine maximum RAM capacity, RAM’s operating frequencies, which generation of RAM is supported, how many RAM modules can be installed.

Note that CPUs usually officially support a fairly low RAM frequency, but as long as the motherboard supports it, they usually can operate at higher frequency without any trouble.

RAM Overclocking

Overclocking RAM is done by increasing frequency and reducing timings. That can potentially make the system unstable, so the voltage is increased to compensate. Note that this puts additional stress on the memory controller, especially if multiple modules are installed.

Most high-frequency RAM kits come with factory overclock in the form of one or more XMPs – Intel Extreme Memory Profiles – they are basically presets with frequency, timings and voltage. That memory kit underwent factory testing with those settings and it’s guaranteed to operate in a stable manner. All you have to do is to select the XMP in BIOS.

How to choose RAM

First, figure out how much RAM do you need.

For modern gaming, 8 GB is enough, including Witcher 3 at maximum settings, though you might be cutting it close in some of the “heavier” titles. 

Some games eat more RAM than others, and that doesn’t necessarily happen because of better graphics – some games are just poorly optimized. Eventually, there will come a time when 8 GB RAM will not be enough.

16 GB is recommended if you can spare the extra expense. If your motherboard has 4 RAM slots, you can always go for 2 x 4 GB modules now, and move to 4 x 4 GB later. 

More RAM might be required if you intend to run a lot of background applications, or perform any professional work that benefits from more RAM.

What happens if there’s not enough RAM? When the system runs out of RAM, Windows starts moving extra data to the Page File – a special file on your hard drive. This takes time and reduces performance.  Storing Page File on an SSD helps to mitigate that negative impact, but since even the fastest SSDs are much slower than slowest RAM, there will be a steep decline in game’s performance.

Is there a point where adding more RAM won’t do anything? Not exactly. Windows, with all its flaws, is a fairly smart operating system, and it will utilize unoccupied RAM by caching frequently accessed data to improve response time.

For example, the system keeps track that you’re frequently playing the same game every day, so while idling Windows will pre-load game’s files into RAM just in case you decide to launch it. 

And if Windows needs RAM for something else, it will remove the cached data without a second thought, so there’s no harm in doing this.

That said, just having the game on an SSD is a much more economical solution.

General Recommendations

You always want to go for the maximum amount of channels your motherboard and CPU can support. Usually this means two channels, so you want at least two modules.

Go for dual ranked memory, when possible. Or go for a RAM kit with 4 modules from the get go. This will improve performance. 

Once that is figured out, try to balance cost, frequency and timings. Just keep in mind the maximum frequency supported by your system.

Usually, going for high speed RAM is not worth the expense, especially for gaming, but sometimes you can get faster RAM for nearly the same price.  You can do some manual overclocking later, if you so desire. 

Overall, RAM performance means less for gaming than CPU and GPU, so as long as you have enough RAM in an optimal configuration (dual channel), you don’t have to worry too much about it.

Layer 4 – Storage

HDDs and SSDs fit into this category. They can store a ton of information for their price, but they also take a lot of time to access, and their data transfer rate is comparatively low. 

They keep all the data safely stored even without any power.

Simple Analogy

Imagine the CPU is an engineer, working in a workshop somewhere in a city. He also rents a large storehouse (storage) on the outskirts of the city. Storehouse is cheap to rent, and has a lot of space. But transferring stuff between the workshop and the storehouse means a 30 minute ride. Obviously, the engineer wants to avoid that hassle as much as possible, so when working on a project, he tries to cram as many tools and materials in his truck as possible.

Then the engineers takes those materials to his workshop and unloads them on shelves (RAM). On the other side of the workshop, there’s engineer’s working desk (CPU cache).

Engineer grabs a few tools and materials that he will likely need soon, and carries them to the working desk. The desk has a lot of drawers (Level 3 CPU Cache), and there is also some space on the desk’s surface (Level 1-2 cache).

Engineer sits down and starts working. His hands are memory registers. To work on something, the engineer has to take it in his hands first.

Engineer keeps working and realizes that to do next part he needs another material or another tool. First he looks on the desk’s surface, as it would be closest to get from. If it’s not there, he starts going through desk’s drawers.

If Engineer finds it, it’s a Cache Hit and he keeps working. If he doesn’t, it’s a Cache Miss, and he just wasted time. He will begrudgingly stand and walk to the other side of the workshop to get the needed tool or material from one of the shelves. While he’s there, he’ll grab some other tools and materials.

When the engineer finishes working (power down), he cleans up the workshop, throwing away all tools and materials he used today. If something could still be useful, he takes it to the storehouse (permanent storage).

£800 Build: Balanced Gaming

Recently I was contacted by a UK resident, asking for some help building a gaming PC. They did not set a specific budget, but instead provided me with a sample build and asked for my input. That build had good intentions, but lacked any direction, to put it mildly.

So instead I suggested a build with a similar price, but with more focus on gaming performance and overclocking. Meet the Balanced Gaming Build.

CPU: Core i3-8350K

This is a recently released mid-tier Intel CPU. Intel CPUs are known for their excellent per-core performance, and this CPU can be overclocked. 

Overclocking makes the CPU work at a higher frequency (making it more powerful), at the cost of drawing more power and producing more heat. Maintaining a stable and effective overclock requires that other components, such as Motherboard, Cooling and RAM, be of higher quality as well. So pretty much the whole build is centered around overclocking.

When pushed far enough, overclocking will also reduce CPU’s lifespan, but PC components usually go morally obsolete long before reaching the end of their lifespan.

This i3 is the cheapest “decent” CPU you can get. It is still fairly expensive, but it offers excellent performance / cost ratio, and overall makes for an economical choice right now. 

For example, a 6-core i5 8600k costs £90 more, but with equal clock frequency it has only slightly better performance in games.

Another example: 6-core i5 8400. It has maximum Turbo Boost frequency of 4.0 GHz, same as stock 8350k. They also cost about the same, with i5 8400 being marginally more expensive.

However, i5 8400 cannot be overclocked, and in most games will lose to overclocked 8350k.

Six cores might be more relevant in the future, where we could potentially see more multi-threaded games, but it doesn’t make sense to pay extra now just so you could maybe have better performance in a few years. At that point, it would be It would be better just to upgrade to another CPU.

Currently, all motherboards that can work with Coffee Lake CPUs have Z370 chipsets. They allow to overclock “k” CPUs by multiplier. Motherboards with cheaper B- and H-series chipsets are not available yet.

When they do become available, i5 8400 might become a more competitive choice, because going for a non-overclocking build would significantly reduce overall cost.

But right now, you’re paying a premium for a motherboard that can overclock regardless of whether you actually intend to overclock or not. In these circumstances, it doesn’t make sense to go for i5 8400. 

CPU Cooler: ARCTIC Freezer 7 Pro Rev.2

This inexpensive cooler is powerful enough to easily handle overclocked i3 8350k. It comes with a high quality MX2 thermal compound, and the fan uses a Fluid Dynamic bearing, which makes it very durable. Comes with 6 year warranty.

Motherboard: MSI Z370 SLI PLUS ATX

This motherboard is a bit unorthodox choice for this build, because clearly we’re not going for SLI. Moreover, SLI is not something I’d recommend to anyone outside of some very specific circumstances. 

However, even if we are overpaying for unnecessary SLI capability, this motherboard still makes a great pick. It is fairly inexpensive, and its 10 phase power delivery system will ensure stable and powerful CPU overclock. Heatsinks on the VRM system further improve overclock quality and system longevity.

MSI motherboards come with loads of useful performance-enhancing features, and they can automatically overclock the CPU in one click, so it will be super easy even for those who’ve never overclocked before.

Memory: Patriot Viper Elite 8GB (2 x 4GB) DDR4-3000

This is a high quality, high speed memory that will ensure the 4-core CPU will not become (as much) of a bottleneck in highly-threaded applications.

8 GB might not be as comfortable as 16 GB would, but it should be enough for the next few years. We are more or less trying to stay in a budget, after all.

SSD: Samsung 850 EVO 250GB M.2-2280

This is the cheapest decent SSD available at the time and place, costing as much as MyDigitalSSD BPX 128 GB.

850 EVO’s 250 GB is enough to house operating system and other programs, and a couple of games, but the rest of the storage will have to be handled by a hard drive.

Storing the Operating System and programs on an SSD significantly improves performance and load times, that’s why having at least some form of SSD is highly recommended.

However, if you don’t care about load times at all, you can in fact save a lot of money by not getting any SSD at all, though this approach becomes less and less popular.

HDD: Toshiba 1TB 3.5″

Toshiba makes the most reliable HDDs at the moment, with excellent quality to cost ratio. A perfect choice for any mainstream build.

Video Card: MSI GeForce GTX 1060 3GB GT OC

AMD and nVidia often bump heads at this price point, depending on GPU performance and the amount of available VRAM.

VRAM is a weird beast. You either have enough or you don’t. If you have enough, adding more RAM won’t do anything for you. If you don’t have enough, gaming performance will plummet. 

However, it is always possible to reduce certain settings to reduce VRAM consumption. Resolution, anti-aliasing and texture quality are the biggest VRAM eaters.

First up is GTX 1060 3GB variants. The GTX 1060 itself offers excellent performance, and 3 GB of VRAM is enough to play vast majority of current titles at good settings at 1080p resolution.

Right around the same price point, there is RX 570 4 GB. It performs slightly worse than GTX 1060, but some extra VRAM may come in handy later down the road.

Then there is RX 580 4 GB. It is as powerful as GTX 1060, but ~10% more expensive than GTX 1060 3 GB. 

Finally, there is ~28% more expensive GTX 1060 6 GB version, which also has about 5% better performance than a slightly cut down chip of the GTX 1060 3 GB.

If you don’t plan on using resolution higher than 1920 x 1080, and you’re fine with occasionally turning down a few specific settings, GTX 1060 3 GB makes for a really economical choice. 

It’s not as future proof as it could be, but even if you are faced with VRAM issues in a few years, it would make more sense to sell your GTX 1060 3 GB then, and get another Graphics Card, which should both offer better performance and come with more VRAM. 

Otherwise, RX 570 and RX 580 seem like good “in between” solutions. GTX 1060 6 GB seems hard to justify.

MSI GTX 1060 3GB GT OC in particular offers good clocks and cooling for its price, though I wish it had a dedicated heatsink for the VRM system.

Case: BitFenix Nova ATX Mid Tower

This a really cheap case. There is nothing particularly wrong with it; it does what a case is supposed to do, but it’s not necessarily the most convenient in terms of assembling and maintenance.

If you don’t mind spending some extra time fiddling with cables and crawling around with a screwdriver, then this case is perfectly fine. Otherwise, I suggest something more expensive, like Zalman Z3.

In addition to more convenient assembly and cable management, more expensive cases are more likely to have higher quality ports on the front panel, and they often come with nice extras, such as fans, dust filters and removable carriages for HDDs and SSDs.

Power Supply: Corsair Builder 430W

Corsair makes excellent, reliable and durable power supplies, though this is one of their cheapest products.

430 Watt may seem unusually small, but GTX 1060 is not particularly power-hungry,  so it should be more than enough to power overclocked CPU and GPU, and have plenty of juice left for other components.

Comments and Considerations

This is definitely a fine gaming build, but I am not as happy with it as I was with the previous $2200 “Make your dreams come true” build.

Things that I would consider changing:

Getting a better case or at least an extra case fan. The BitFenix Nova comes with only one case fan at rear exhaust. I would like to add one intake fan to the front panel to supply some fresh air to the Graphics Card.

Getting an extra cooler for Motherboard’s VRM system to ensure stability and longevity of the overclock. It is highly likely an unnecessary overkill, as 10 phases and heatsinks should already provide more than enough durability, but better safe than sorry. What’s a $10 fan and a couple of paper clips compared to peace of mind?

Normally I would just pick a CPU Cooler that directs some airflow towards the Motherboard, as I did with the previous $2200 Build, but in this time and place there were no coolers available that would be able to handle an overclocked 95 Watt TDP CPU and still fetch a modest price.

Getting a higher grade Power Supply. While there is no reason to doubt Corsair in this regard, I would feel a bit more comfortable with a 500 or even 550 Watt PSU. It would also somewhat “future proof” the Power Supply itself, making it more relevant in future builds, which could be potentially more power-hungry.

Power Supplies are also usually more efficient at load that is significantly below maximum.

Getting a GPU with more VRAM. Enough said about it in the GPU section.

This build is not as efficient as it could be. While overclocked i3 8350k offers excellent performance, it has no Turbo Boost, so it runs at higher frequency ALL the time, drawing more power and deteriorating faster than it should.

There is a way around this problem: MSI motherboard software allows the user to create some keybinds to change the CPU Multiplier. So while doing some light office work, you can switch the CPU into lower frequency mode, and crank it up while gaming.

This build is not as “future proof” as it could be either. Bare minimum of RAM and VRAM, 4-thread CPU, bare minimum power supply, no VRM heatsinks on the GPU. There’s no airflow through Motherboard’s VRM either, though it’s the smallest problem, and even then it could be easily corrected.

However, not every build has to be “future proof”. In fact, “future proof” builds are hard to justify economically. Overclocked i3 8350k is enough to tear through vast majority of current and upcoming titles. So is GTX 1060 3GB – with a few concessions.

It will be ultimately cheaper and better to upgrade specific components when it becomes necessary, swapping them out with the next generation of mainstream components with good value.

This closes this build. If you’d like for me to make a PC Build for you, check out my PC Building Services.