How to Pick the Right GPU for your Computer

By Samuel Wilson

Now that a tower has been selected, the computer components for the build will now have a “home”. The next step is to determine whether a dedicated GPU (Graphics Processing Unit also known as Graphics or video card) is needed. Determining if a computer build needs a graphics card, depends on the intended purpose of the PC. Earlier on in the series, different use cases and build types were discussed in detail visit (http://goo.gl/cjzHcm) to review that material.

For those that decided to go with a budget build because of light computer usage and minimal system requirements, having a GPU isn’t always necessary. Most modern motherboards have built in integrated graphics, so purchasing a dedicated graphics card isn’t a requirement. On the other hand, an APU may have been selected for a budget build for various reasons. Some of these reasons include: having a small budget, but wanting to do some light gaming or having the ability to experience HD content.

As it was previously noted, some CPU’s have integrated graphics such as the AMD Accelerated Processing Units (APU’s). The A8-7650 APU is an example of this; most APU’s will allow you to perform light gaming, watch videos, and do some multitasking on your PC.

There are two manufacturers of graphics cards, NVIDIA and AMD, but there are different vendors with their own version of the various GeForce (NVIDIA) and Radeon (AMD) cards. Generally, graphics cards will be labeled something like this: EVGA GeForce GTX 750 Ti 2GB 128-Bit GDDR5 and MSI Radeon R9 390X 8GB 512-Bit GDDR5. EVGA and MSI are the vendors, NVIDIA (e.g. GeForce) and AMD (e.g.  Radeon) the manufacturers, the model number (e.g. R9 390X), size of the memory (e.g. 8GB), memory interface (e.g. 512-bit), and memory type GDDR5.

For most mid-range and high-end builds, a GPU will be needed for gaming, editing video/multimedia, or watching a great deal of HD content. GPU selection will largely be based upon the allotted budget, video outputs needs (i.e. Single or Multiple HDMI and/or DVI outputs), and how CUDA cores the GPU has. CUDA cores, are for NVIDIA based GPU’s, higher is better and OpenCL is associated with AMD based GPU’s.

When looking to purchase a GPU there are a lot of terms, but here is a brief overview of some of the essential terms:* Interface: This will list what PCI interface the card is using such as: PCI, PCIe 2.0, and PCIe 3.0.Your motherboard has to be compatible with that particular Interface.* Core clock: is the Frequency that the GPU is running at, you can think of this in the same manner as the CPU. Again, higher is better (regarding speed) because this allows images to be rendered faster.

* Memory Interface: is available in 128-bit, 256-bit, 384-bit, and 512-bitbus widths and this is used to help calculate the total amount of data that can be passed at once (bandwidth). For the most part, higher bit rates mean there are more lanes for the information (data) to travel. Total bandwidth is highly dependent on the width of the card bus (the bit rate of the card bus) and the speed of the memory on the graphics card.

Depending on the workload, the size of the bus width may not add a huge performance increase. A wider bus width, will come in handy if lots of detail and information need to be processed by the GPU at once. Certain gaming titles that are played on the highest settings or various multimedia applications will benefit from having a higher memory interface on the GPU.

* Memory clock: is the speed in which the card’s memory operates at, higher is better if added performance is desired.

* Memory bandwidth: is the how much data that can be accessed and stored (at once) from the memory that’s on the graphics card. You will also see the amount memory and the memory type that is being used on the GPU, for example 4GB DDR3, and 4GB GDDR3, and 4GB GDDR5. GDDR5 provides more bandwidth than DDR3 and GDDR3, so keep that in mind.

* Overclocking: is pushing/configuring the GPU beyond the stock settings that the manufacturer assigned to the device. This is done in order to get added performance from the GPU. This will benefit users that game and/or perform multimedia tasks.

Each card will require a certain amount of power in order to operate, this can be referred to as Thermal Design Power (TDP). A properly rated power supply is needed to ensure enough power is being delivered to all of the computer components. It’s necessary to check power specifications of the GPU prior to purchase. Cards that require additional power will need to be plugged into the power supply and may need additional cooling if the stock GPU cooler isn’t sufficient. The extra power draw of the card, usually causes additional heat as a result, so keep that kind. Some GPU fans/coolers are noisy and/or bulky, so make sure there’s enough room around the GPU for other expansion cards. Along with that, make sure the card can actually fit in the case; some GPU’S are too long and won’t end up fitting inside the case.

More than one graphics card can be used in a system at one time (if your motherboard supports it); for NVIDIA GPU’s, they would operate in SLI or in CrossFire on AMD GPU’s. Using two GPU’s doesn’t give you two times the performance, it generally provide a 20-50% increase. I’m not going to dive too much into this topic during this section, but here are a few things to keep in mind. You cannot use dissimilar cards with NVIDA GPU’s, they need to be the same type of card/model number, for the most part. For AMD GPU’s, you can use various cards that are within the same family. At a later point in time this will be discussed in greater detail. For the moment, the best option would be to get the single best GPU for the allotted budget, that’s where the greatest performance gain will be.

One of the best things to do, is to look at the model number, then look up the specifications for that card, and then pay close attention to what the vendor is advertising for that version of the card. Sometimes, lower end GPU’s will have higher clock speeds to try and “make up” for other areas they lack in. Try to compare and contrast cards without confusing and frustrating yourself.  This doesn’t have to be an overwhelming process. Here are some great AMD Radeon GPU’s from MSI (listed in order of price, low to high) for different build types: R9 280x, R9 390X, and R9 Fury X 4G (www.msi.com and www.amd.com). Stay tuned, as I discuss how to pick out a power supply for a computer build.

For more information visit newburghtechgroup.com.