The processor on a high-performance graphics card is called the GPU. Its design is fundamentally different to the kind of processor used to run a computers central functions known as your CPU. In a regular CPU, there are relatively few processor cores, usually between 4 and 16, with each processor core operating at a high clock frequency. In a graphics card, the GPU will have a very high core count, often as high as 3500 or more cores but each core operates at the far lower clock frequency. It is these large number of core that is significant about choosing a graphics card for a video editing PC.
Adobe Premiere Pro uses GPU acceleration for many of its more complex and compute-intensive tasks; this is the most efficient way to handle such functions because most image/video processing tasks can easily be broken down. The CPU has the role of marshalling these jobs to the GPU and deciphering the output. Think of it like this, if you wanted to load a removals van with the contents of a house as quickly as possible, would you rather have the “worlds strongest man” (CPU) or a team of 100 ordinary people (GPU)? Adobe Premiere Pro video editing software would have the job broken down by the group of 100 to get it done quicker.
It’s essential to maintain a balance between GPU and CPU performance as a bottleneck can occur if one is more powerful than the other. If you over specify the CPU, then not all of its power will be used, as the GPU will be working at maximum and won’t be able to pass enough work to the CPU. Careful system design regarding the CPU / GPU balance will reward with the best price/performance system.
A system based on the Z370 chipset and the i7-8700 processor will perform well with a single GPU, even a top end consumer model such as the GTX1080ti.
Systems with multiple GPU will benefit from the increased performance of the X299 platform because of increases in the CPU core count and also because of the higher number of PCIe lanes available on that platform.
Use of multiple GPU in a high-performance video editing system will be quite heavy on I/O throughput so moving up to the 28 PCIe lanes of the i7-7820X or the 44 lanes of the i9-7900X will bring performance increments.
Often the performance increase observed when moving from a single GPU system to a dual GPU system is significant. On a high specification X299 platform, it can scale almost to double the performance of a single card system.
For Adobe Premiere Pro to be able to make use of the graphics card, it must support either Cuda or OpenCL. Nvidia cards support Cuda, and AMD cards support OpenCL. Cuda comes out as the clear winner in straight up performance tests with a variety of codecs. We would recommend users choose a Nvidia based GPU.
Any graphics card will help improve performance. Ideally, if you install more than one GPU in your PC, you should try to keep to the same model, but system performance can be boosted even with different cards as long as they are both using the same vendor’s chipset, i.e. both Nvidia running Cuda.
Aim to use graphics cards with high quantities of onboard video memory (VRAM). If your GPU has insufficient video memory, then your PC will be forced to use the computers CPU to process even when you have switched on GPU acceleration, this can happen partway through a job. For this reason, we recommend cards with a minimum of 6GB but ideally aim for 8GB or higher.
Systems utilising more than one graphics card don’t need to have the cards linked with an SLI bridge. Don’t install more than two cards if you are using Nvidia GTX cards. Nvidia hasn’t designed the latest 10xx series GTX cards to be used in 3-way or 4-way configurations, and although some users have reported success, we have experienced system instability with these configurations.
For high-performance systems, consider using Nvidia Quadro cards. The cards are designed to be used as Cuda GPU, so the cards and drivers have been optimised along these lines. The cards are also equipped with far more substantial quantities of video memory and can be used in 3-way and 4-way configurations. Quadro cards also support 10-bit colour which can be beneficial for those working in studio quality settings. GTX cards only support 8-bit colour.