Simple computing tasks can be performed by CPUs alone, but complex tasks require the help of dedicated devices such as Graphics Processing Units (GPUs).
GPUs too, however, have their limits, and one GPU alone might not be able to get the job done for highly demanding tasks. This made people dream of a time when they would be able to combine the power of multiple GPUs for intensive computing functions.
In the world of technology, it doesn’t take too long for dreams to turn into reality, and the SLI technology is just one such realization of a long-held computing dream. Let’s find out if can you SLI different cards or not.
What is SLI?
NVIDIA is the biggest GPU manufacturer on planet Earth, which introduced the Scalable Link Interface (SLI) technology in 2004, which enables users to merge 2-4 graphics cards on a single computer system. The combined horsepower of these cards provides increased performance for demanding applications like video games or complex 3D rendering tasks.
How SLI Work?
SLI works by utilizing the principle of parallel processing. When GPUs are connected to each other through an SLI configuration, they share the graphics rendering workload between themselves. There are two ways this workload breakdown works:
- Split Frame Rendering (SFR)
Every frame of a 3D application is divided into sections in the SFR mode. Each graphics card in the SLI configuration is assigned a particular section to deal with. This allows all GPUs to work on different parts of the same frame at the same time for improved performance.
- Alternate Frame Rendering (AFR)
Alternate Frame Rendering, on the other hand, allows each GPU to render whole frames individually but in an alternating fashion.
If that confuses you, consider a 3-GPU SLI configuration in AFR mode, which will work like this:
- First GPU will render ‘Frame 1’.
- The second GPU will render ‘Frame 2’.
- The third GPU will render ‘Frame 3’.
- First GPU will render ‘Frame 4’, and so on.
This process further reduces rendering time, boosting the speed and performance of graphics-intensive applications.
SLI vs Crossfire
With NVIDIA taking charge in multi-GPU configurations, it was only a matter of time before their bitter rival AMD also dabbed their toes in these waters, and they did that by developing their own technology called ‘Crossfire’. Those considering a multi-GPU setup would do well to familiarize themselves with these two technologies and their key differences.
- Brief Introduction to Crossfire
Crossfire is a multi-GPU technology developed by AMD, similar to SLI. Multiple AMD graphics cards can be linked together to improve overall performance. Crossfire allows you to build a robust system with the processing power to handle graphics-intensive programs like games and professional 3D rendering. Crossfire, like SLI, connects multiple graphics processing units (GPUs) together and divides up rendering tasks among them via an inter-GPU communication bridge.
- Comparison between SLI and Crossfire
While SLI and Crossfire share the same fundamental goal – to improve graphics performance through the use of multiple GPUs – there are notable differences between them:
- Compatibility: When using SLI, you can only connect two GPUs of the same type. They need to be identical and made by the same company. Crossfire, on the other hand, offers a little more leeway. It enables you to match up similar cards from different sets.
- Motherboard Support: SLI requires NVIDIA-approved, SLI-capable motherboards, which feature a dedicated SLI chipset. Crossfire offers greater compatibility and can be used with more motherboards because it requires only multiple PCIe slots to function.
- Rendering Method: Both technologies support both Split Frame Rendering (SFR) and Alternate Frame Rendering (AFR), but NVIDIA’s SLI favors AFR. AMD’s Crossfire, on the other hand, is more adaptable and can switch between the two rendering methods as needed.
- Software Support: Both SLI and Crossfire require software support from game developers to fully utilize multi-GPU configurations. However, thanks to NVIDIA’s proactive approach to working with developers, games, and software are more likely to support NVIDIA’s SLI.
Use Cases for Both SLI and Crossfire
SLI and Crossfire are utilized in situations where computing and processing needs are very high, such as:
- High-end Gaming: Hardcore gamers can benefit greatly from SLI and Crossfire’s ability to increase performance at very high resolutions and refresh rates.
- 3D Rendering and Professional Graphics Work: Both technologies can significantly reduce the amount of time spent rendering 3D scenes and boost the efficiency of professional graphics software.
- Virtual Reality Applications: High frame rates and low latency are essential for a satisfying virtual reality experience. The use of multiple GPUs is recommended to meet these benchmarks.
- Enthusiast Computing: For those ‘nerds’ who like to push their computers to their limits, SLI and Crossfire provide a way to increase graphics performance.
Your current hardware, the games and programs you intend to run, and your personal preferences are all important considerations when deciding between SLI and Crossfire. Before settling on a solution, you should learn more about the various technologies available and see which one best fits your needs.
Can you SLI different cards?
In most cases, the answer is no; SLI cannot be used with different graphics cards at the same time. The SLI technology requires that two or more cards be of the same kind and come from the same manufacturer (NVIDIA). This means that the cards must be of the same model.
This is due to the fact that various cards can have varying levels of processing speed, memory, and overall performance. This can lead to an imbalance in task sharing as well as inefficiency, which limits the potential benefits that the SLI setup could provide. Therefore, in order to achieve the best possible performance, SLI calls for cards that are identical.
It is important to keep in mind that NVIDIA has made a slight exception to this rule by incorporating the NVLink bridge into their RTX 2000 and 3000 series cards. You can pair two different models from the same series using NVLink, such as an RTX 2080 and an RTX 2080 Ti; however, this is more of an exception than the norm.
From a technical point of view too, it makes sense. It is necessary to have a certain amount of uniformity and compatibility between the components in order to create a SLI configuration that is both effective and capable of delivering high performance. This includes utilizing graphics cards that are identical, possessing a motherboard that supports SLI, and ensuring that adequate power and cooling solutions are utilized.
SLI Capabilities: How Many Cards Can You Use in SLI?
One of the most important questions about SLI setups is how many graphics cards can be used at once to improve performance. The answer depends on the type of cards and how they are set up.
In the early days of SLI, computers could use up to four GPUs at the same time. This quad-SLI setup promised to give very demanding programs a big performance boost. With NVIDIA’s RTX 2000 series, however, SLI support is limited to a maximum of two GPUs. With the release of the RTX 3000 series, NVIDIA made it so that only their high-end RTX 3090 card supports SLI.
The main reason for this change was that managing more than two GPUs in SLI was getting harder and less useful. Few applications could use more than two GPUs well, and the performance gains from using three or four GPUs were often not enough to make up for the extra cost, heat, and power they used.
The most important benefit is the possibility of better performance. Two GPUs working together can process graphic data faster than one GPU alone. This means that graphics-intensive applications will have higher frame rates and smoother gameplay.
With more processing power, you can run games and apps at higher resolutions with more detail. Also, having two GPUs can help your system handle games and apps that are more demanding in the future.
Multiple GPUs will cost a lot more because you need a compatible motherboard, a stronger power supply, and maybe a bigger case with better cooling. Even if a game or app technically supports SLI, it may not be able to use multiple GPUs well even if it does technically support SLI.
The Benefits and Limitations of SLI
SLI’s most visible advantage is a noticeable boost in performance for graphics-intensive applications like games and 3D rendering programs. Gameplay at higher resolutions and with more detail is smoother when multiple GPUs are put to use.
Nonetheless, SLI is not without its flaws. To begin, you’ll need a motherboard that supports SLI and a bridge that can link the graphics processing units together. This raises the price of the system as a whole.
In addition, not all software or games make use of SLI to its full potential. It’s possible that the additional GPUs won’t help performance if the software you’re using doesn’t support SLI.
For users lacking proper cooling management and looking to avoid a fire breakout due to rising temperatures from their computers, SLI is a no-go, as this configuration generates more heat and uses more power than a single GPU system. Users should check their power supplies and cooling systems to make sure they can handle the additional demand, and make sure the computer case can handle the heat.
Despite these restrictions, SLI is still a favorite among gamers who want to break new ground in terms of graphics power. When deciding whether or not to invest in a multi-GPU setup, it is helpful to have a thorough understanding of its features and limitations.
Requirements for an SLI Configuration
It’s not as easy as plugging in two graphics cards to get a SLI setup going. To guarantee the best possible performance from the SLI configuration, certain conditions and factors must be met.
- SLI-Capable Graphics Cards: As was previously mentioned, not all graphics cards support SLI. SLI is only compatible with select NVIDIA cards.
- Identical GPUs: The video cards must be identical in a SLI configuration. This necessitates that they be of identical make and model.
- SLI-Supporting Motherboard: A motherboard that supports SLI and has at least two PCIe x16 expansion slots for the graphics cards is required for this configuration. Keep in mind that only certain motherboards have been approved by NVIDIA for SLI use.
- Power Supply Check: Two graphics cards will increase your system’s power consumption, so make sure your power supply is up to the task. Make sure your power supply can handle the power needs of your graphics cards.
- SLI Bridge: To link the two GPUs together, a special bridge called a “SLI bridge” is required. High-speed communication between the GPUs is made possible by a bridge, which is typically a small printed circuit board that slots into the top of the GPUs.
- Proper Cooling: As the number of GPUs in use increases, so does the need for efficient cooling. If you don’t want your computer to overheat, you must make sure the case has adequate cooling and an effective airflow system.
These setups will also use more power and make more heat, which could lead to higher electricity costs and the need for more powerful ways to cool. And while a second GPU can make a big difference in performance, each additional GPU tends to make less of a difference.
SLI was a powerful technology introduced by NVIDIA to create chain-processing behemoths. While this technology is now defunct and has been replaced by NVLink for newer RTX models, people still utilizing older NVIDIA cards and meeting the hardware requirements can still get a kick out of this configuration for improved performance. However, these benefits need to be weighed against the fact that an SLI setup costs more, uses more power, and might have trouble working with some software. Learn more about computer technology at Vizdeals.net
Is it possible to run two different GPUs together?
Yes. It is indeed possible to have two graphics processing units running inside a single PC, but this setup cannot utilize SLI or even AMD’s Crossfire technology. Instead, each GPU will be able to perform its own tasks and connect to its own display.
Does SLI have to be the same card?
This configuration is mostly utilized for multi-monitor setups, where one GPU powers the main display for gaming or other graphically intensive activities, and another powers additional displays for less intensive activities like web browsing or office software.
Yes. SLI configurations require that all the graphics cards belong to the same model, and that model also needs to be SLI-compliant to begin with.