Games Slow? Easily Figure Out If Your PC Needs A CPU, GPU Or RAM Upgrade

If you're keen to purchase some new gaming hardware for Christmas -- be it for yourself or someone else -- it might not be obvious what piece of tech to get. If your (or the giftee's) machine isn't playing the latest and greatest games at the best of frame rates, there are some rules of thumb that can help make the determination.

First, it's important to understand why newer games don't run as well on older hardware. Beyond the obvious considerations -- more detailed models, high resolution textures and post-process effects such as bloom and motion blur -- many modern games use a rendering technique called "deferred shading".

Without going into extreme details, with deferred shading, the graphics engine takes a snapshot of the player's current view every frame (so up to 60 or more times per second) that collects information about each visible object. This information can be anything from how far away the object is (its depth) to its colour and even the direction each individual pixel is facing.

What do these snapshots look like? Here are some examples from Fear Equation, a game I'm currently working on:

World normals -- basically the direction a pixel is facing, stored in an image's red/green/blue (RGB) channels.

Depth -- how far away each pixel is, relative to the camera, stored as a value from one to zero (or zero to one, depending on the engine). It has a greyscale appearance because 100 per cent RGB is white, while zero is black.

So naturally, the higher the resolution you play a game at, the more information generated per snapshot.

In simple terms, your GPU has to work harder at 1920 x 1080 (around two million pixels) versus 1280 x 800 (one million pixels). Also note that the graphics card may have to process these pixels multiple times per frame. So, if the game slows down dramatically when you increase the resolution, your GPU is the likely bottleneck.

On the other hand, if there's no significant change in frame rate when you alter the resolution, yet the game performs poorly, you'll want to look at upgrading your processor -- especially if it's a dual or single core. While games failed to take advantage of multi-core processors ten and even five years ago, almost all modern games make good use of the extra hardware.

And finally, your RAM. Insufficient RAM usually results in "stuttering". That is, the frame rate might be high, but when you look or move around in-game, the game will freeze for short bursts of time as data is swapped between your hard drive and the memory in your motherboard and graphics card.

If the game takes a long time to load in between levels or areas, look at getting more system RAM -- or even a solid state drive. If it tends to jerk around constantly, that's more indicative of low video RAM as textures and models are loaded in and out dynamically.

If you need a hand upgrading, be sure to check out our previous articles.


    Or maybe you just need an SSD

      An SSD does not give you FPS or improve the quality of the graphics, it can only affect load times (only if the game is stored on the SSD) and alleviate (not necessarily fix) stuttering and loss of FPS caused by not having enough RAM. If buying an SSD has ever improved a game's performance for you then all it has done is improve the speed of your Virtual Memory (the part of your OS drive dedicated to low priority "RAM" and it's overflow when it's full). In which case more RAM would have been a much better choice.

      While the article states that getting an SSD will improve load times it fails to mention this will only improve them IF the game is stores on the SSD. This however is not true for many MMOs (World of Warcraft for example) where while an SSD can improve them a little bit but a good portion of the load time relates to your internet connection and the speed at which the servers can move your character from one server to another.

        Depending on the game, an SSD can help with a lot of extras. (Experience with two twin gaming rigs, albeit one had an SSD and one had a 5400 RPM drive)

        For example, all games have loading screens, whether it be black or a pretty picture to distract you with, but there are a few games where they will only load textures on demand. On a mechanical HDD you might end up spotting textures/texture details popping in, especially on those wide open world maps. The best example of this would be to play an open world racing series called Test Drive Unlimited. If you have a fast enough bike/car, you can literally outrun the loading on a mechanical HDD, and find yourself in a muddy looking world until the texture detail catches up.

        Dynamic music and voice acting, among others are also affected. Star Wars The Old Republic is a good example of this. Walk up to any mission conversation with an NPC on a HDD and you think nothing of it. However, play the same cutscene side by side with an SSD, and the SSD ends the conversation faster than the HDD does. There's these pauses between each voice actor which doesn't happen on the SSD.

        In the end, it depends on how the game was made, but the lack of a mechanical 'seek' really does show in gameplay, not just load times.

        ...will only improve them IF the game is stores on the SSD.
        Would there be any noticeable improvement from having Windows, including DirectX and its plethora of associated libraries, installed on an SSD? At some point the game is going to use them, so in theory there must be some improvement.

        I have no idea, but I thought I'd throw it out there...

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