64-BIT WINDOWS: DX12 & DUAL VIDEO CARDS

GTX SLI

Ashes of the Singularity is the first game to support Windows 10 and DX12. While the game will run with 8192MB RAM, the developer recommends 16384 MB or more. This is another reason we recommend a RAM upgrade.

Now that 14nm video cards are widely available we expect a flood of DX12 games now that there are more than 300 million Windows 10 users.

GeForce 600 series and above will be supported and Radeon HD 7000 series and above will be supported. The new 14nm cards will revolutionize PC gaming. 3820×2160 panels still need multiple video cards to achieve an acceptable frame rate with recent titles.

DX12 uses multiple video cards differently. CFX and SLI are OK for DX9, DX10 and DX11 but they are obsolete with DX12. The vast majority of gamers use a single video card and not have issues.

The DX12 SPI uses a concept called waves to render a frame instead of the old alternate frame rendering approach. This makes it easier to use multiple CPU cores as GPU cores to render a frame.

There is a lot of confusion over the use of dual video cards and DX12, In short, dual CFX and SLI are fine for DX9, DX10 and DX11 but DX12 they are not compatible.

Dual GPU cards will also be affected as they are technically the same as CFX and SLI setups.

AMD and NVIDIA drivers can manually disable CFX and SLI in their respective drivers.

The main complaints come from those who have 2560×1440 and 3820×2160 panels who have DX11 and DX12 games. Unfortunately drivers are not capable of switching CFX and SLI on and off as required.

Perhaps future drivers will be able to switch modes of operation but for now the problem has to be manually adjusted.

This is also the main reason the vast majority of PC gamers using one single video card and stick with 1920×1080 panels. It may not be until 2018 before a single video will be powerful enough for 3820×2160.

DIRECTX 12

Windows 10 includes the new DirectX 12 that was announced back in March 20, 2014. At the conference Microsoft showed the Xbox One game called Forza 5 running on Windows and a GeForce GTX Titan Black video card. NVIDIA has marketed their GTX 980 and 970 as DX12 cards. We expect that it may take 18-24 months for games to be developed that really show DX12’s capability. Microsoft worked on DX12 for over 2 years before then announced it because its a complete rewrite from scratch.

Recall the problems with game compatibility the plagued Windows 8 before the 8.1 update was finally released  Microsoft has indicated that backwards compatibility will be better. We tested a few old games and generally the compatibility is excellent with Windows 10. Steam and Origin et al all work as well. Microsoft has worked hard to be sure that the mistakes with the early release of Windows 8 are not repeated.

The modular architecture is more capable with threaded programs. Most games today and multithreaded so this the direction games and hardware are moving. Early demonstrations are encouraging. DX12 is also more power efficient with some examples showing a 50% reduction in GPU load. This bodes well for more sophisticated and realistic game environments.

DX12 will work with GeForce 500 series and above and Radeon HD 7000 series and above fine. Older cards are now obsolete and should be replaced ASAP. Realistically, no game will require DX12 so users of older high-end cards will able to play games reasonably well. Even in 2015 many games still work with DX9 video cards. A modern 28nm video card is much more energy efficient so its pays for itself in power savings over time.

ASYNCHRONOUS SHADERS

DX12 introduces a new idea called asynchronous shaders. This works by expanding on the threads and taking more advantage of modern CPU and GPU architectures. This way the amount of time to render a given frame in a game can be done more quickly. It also means that developers can consider new options such as more lawns and other hard to render objects.

DX12 is designed to work well with modern processors. Recent consumer CPUs from Intel now feature more than 16 hyperthreaded cores.