A computer system comprises several hardware components, working together to deliver the required performance. Some of these components possess incredible power, which helps in data processing. A system’s CPU uses RAM to handle the temporarily stored data quickly. The GPU unit also processes important graphical data needed to render graphics. Since regular DDR cannot handle complex data and higher bandwidth, GDDR is dedicated to the GPUs.
Graphics Double Data Rate (GDDR) is one of the variants of SDRAMs. GDDR serves as a dedicated memory for the GPUs to remove bottlenecks in data handling. These units have been around for a few decades, yet many users lack knowledge. Hence, this article will help you explore the details of GDDR, its types, and necessary comparison.
GDDR And Its Significance
GDDR is a shortened word for Graphics Double Data Rate. It belongs to the Synchronous Dynamics or Graphics Random Access Memory family (SDRAM /SGRAM). The DDR or Double Data Rate is a feature that refers to the data transmission potential of GDDR. The data transmission speed remains constant on changing clock signals. With the help of higher memory bandwidth, the data transmission speeds double.
GDDR memory does the same for the GPU as RAM does for the CPU. It is a temporary storage for the graphical data file and allows faster retrieval. It is specifically optimized for the GPUs to optimize the graphics processing. This enables the GPU to handle graphic-intensive applications like gaming, video editing, music production, etc.
Why Is GDDR Memory Used?
A system’s graphical processing power decides how it will render visual data on the screen. This process is intensive and needs a specialized memory. Using the system’s core memory (RAM) for graphical data bottlenecks and other activities. This is not desirable when the system is being used for graphic-intensive work. Hence GDDR memory is allocated to the GPU.
It helps relieve the calculation process by providing a higher bandwidth than the system’s memory. As a result, smoother graphics are rendered and displayed on the system’s screen. Users can set the graphical settings at maximum without fearing lag in graphical performance. GDDR is also known for its power-efficient operations, which help attain power savings.
GDDR has gone through a brief period of advancements, with several versions introduced to the market. Starting from DDR SGRAM, the GDDR6 is the latest generation of GDDR memory. The GDDR5 and GDDR6 memories are the most popular series in the GPU market right now. We will explain both the memories to understand them in detail.
GDDR5 Series
The GDDR5 memory was introduced to the market in 2010 and has been popular since then. This memory offers significant upgrades over the previous DDR4 memory. It offers very low latency, built on the 20 nm fabrication process node. This memory achieves a data transfer rate of 8 Gb by improving the bandwidth. This memory was specially designed to handle graphical data for the newer 4K screens.
To match the performance of the newer GPUs and displays, the GDDR5X version was introduced. This memory is based on the same 10 nm fabrication process with an extra capacity of 16GB per die. It allows the GDDR5X memory to attain a speed of 10 to 12 Gbps, nearly double of DDR5 memory. This high-density memory became popular for high-end GPUs, including the Nvidia GTX series. The power efficiency of the GDDR5 memory was already better, which was further improved in the GDDR5X version.
GDDR6 Series
Following the success of the GDDR5 series, the GDDR6 series was introduced. These memories were more advanced and tuned for the powerful GPUs of the modern age. This memory is based on the latest 10 nm process node. A dual-channel count offers a density of 32 GB per die. The GDDR6 memory boosts the data transfer process at a speed of 16 Gbps. These memories were the first ones to support the AI accelerator technique in GPUs.
With the arrival of current generations of GPUs, DDR6X memory has been developed. With a minimal upgrade over the GDDR6 memory, this memory focussed more on the network signaling process. For the GPUs used for internet-connected games or applications, the PM4 multilevel signaling of GDDR6X delivers unbelievable clocking speeds. The system’s data transfer speed was also improved up to 18 to 20 Gbps, allowing faster processing of graphic files. It is also more energy efficient than the GDDR5 memories running at a 1.3V supply.
Comparison Table Between GDDR5 And GDDR6
Both GDDR5 and GDDR6 belong to different generations. As a result, some differences between these two versions affect their performance. To understand the differences between GDDR5 and GDDR6 memories, it becomes crucial to go through the following comparison table.
| Parameters | GDDR5 | GDDR6 |
| Density | Up to 8 GB | 8 GB to 16 GB |
| Bandwidth | 32 GB/s | 72 GB/s |
| Burst length | 8 | 16 |
| Node fabrication process | 20 nm | 10 nm |
| Total number of channel | 1 | 2 |
| Array Prefetch | 32 bytes per cycle | 64 bytes per cycle or 32 bytes per channel |
| Voltage | 1.35 V to 1.5V | 1.25V to 1.3V |
| I/O width | x16 or x32 | X8 or x16 |
| Per pin data rate | 8 Gbps | 14 to 16 Gbps |
| Available memory capacity | 512 MB, 1 GB, 2 GB, 4 GB, 8 GB | 8 GB and 16 GB |
| Access granularity | 32 Bytes | 32 Bytes per channel |
| VRAM capacity | 11 GB | 48 GB |
| Clock speed (boosted) | 1540 MHz | 1770 MHz |
| Effective memory clock speed | 8000 MHz | 12,000 MHz |
| Manufacturing brands | ELPIDA-Micron Technology, Samsung, and SK Hynix | Micron Technology, Samsung, and SK Hynix |
Difference Between GDDR5 & GDD6
The comparison table provides all the necessary specifications of the GDDR 5 and GDDR6 memories. Having gone through the comparison table, we can now easily differentiate between certain parameters of GDDR5 and GDDR6.
1. Graphic Card Compatibility
Each memory version has been specially developed for certain GPUs. This is done to match the graphical processing power of the memory with that of the GPU.
2. GPUs With GDDR5 Memory
The GDDR5 memory was first used with the AMD Radeon HD 4870 card. Since then, both AMD and Nvidia GPUs have been successfully paired with GDDR5 memory. Following are some of the popular GPUs used with GDDR5 memory.
| Brand | GPUs |
| AMD | Radeon HD 4870 |
| Radeon HD 7990 | |
| Radeon RX 4860 | |
| Radeon RX 580 | |
| Radeon RX 590 | |
| Radeon HD 4750 and 4770 | |
| Radeon R9 295X2 | |
| Nvidia | GTX Titan |
| GeForce GTX 980 Ti | |
| GeForce GTX 1050 Ti | |
| GeForce GTX 1060 | |
| GeForce GTX 1070 Ti |
3. GPUs with GDDR6 Memory
GDDR6 was developed for demanding applications, and hence it is compatible with several high-end GPUs. Nvidia was the first brand to incorporate this memory into their GeForce 2000 series. Since then, both Nvidia and AMD have offered midrange and high-end GPUs with this memory.
| Brand | GPUs |
| AMD | Radeon RX 5300 |
| Radeon RX 5500 and 5500 XT | |
| Radeon RX 5600 XT | |
| Radeon RX 5700 and 5700 XT | |
| Radeon RX 6700 | |
| Radeon RX 6800 XT | |
| Radeon RX 6900 XT | |
| Nvidia | GeForce GTX 1630 |
| GeForce GTX 1660 Ti | |
| Titan RTX | |
| GeForce RTX 2070 Super | |
| GeForce RTX 2080 Ti | |
| GeForce RTX 3060 Ti | |
| GeForce RTX 3070 |
4. Performance
When specifications are compared, GDDR6 looks more promising than GDDR5. This statement is true to an extent since the GDDR5 is based on older fabrication process nodes. GDDR6 comes with several updates, making it more efficient than GDDR5. GDDR6 shows more data transfer rate per pin, compared to GDDR5. With higher memory capacity, the storage of temporary graphical data is improved in GDDR6. However, GDDR5X and GDDR6 show a minimal difference in the performance. Hence, users can choose a GPU with GDDR5X memory to experience better power at a cheaper rate.
5. Power Consumption
The GDDR5 and GDDR6 memories are designed to consume power efficiently. GDDR5 shows better power efficiency compared to the previous generations of graphic memory. It saves energy with automatic power down whenever there are zero activities. Depending on the data load, this memory operates at a minimal 1.35V and a maximum of 1.5V. GDDR6 further improved the power efficiency to reduce power consumption with high-end GPUs. These memories come equipped with power-saving features which further improve energy efficiency. Running at 1.25V to 1.3V power, the memory ensures longer battery life for portable devices and better energy savings for PC systems.
6. Bandwidth
The bandwidth of GDDR6 is more than that of GDDR5 due to the presence of multiple channels. GDDR5 being an older generation memory, shows less bandwidth which is still enough for the lower mid-range GPUs. The bandwidth of a minimum of 32 GB/s is enough to handle most of the rendering data. The GDDR5X, however, shows improved bandwidth, making it suitable for midrange and upper-midrange GPUs. With dual channel configuration, GDDR6 easily offers a minimum bandwidth of 72 GB/s. The overall bandwidth changes depending on the type of GPU used. This ultimately affects the actual data transfer rate of both GDDR5 and GDDR6 memories.
7. Clock Speed
Clock speed is considered as the most important factor of any GPU. The operational frequency of the memory module controls the data transmission rate and overall performance. GDDR5 memory has a base clock speed of over 1400 MHz, which goes up to 1540 MHz under boosting. GDDR6 has a base speed of 1650 MHz, which goes up to 1770 MHz under boost. This difference is noticeable when using heavy games or applications. Both memories also have different effective memory clock speeds. GDDR5 can achieve 8,000 MHz speed, while GDDR6 exceeds the 12,000 MHz limit. The clock speed under overclocking supported GPUs incredibly boosts the system’s performance.
8. Gaming Speed
The gaming speed matters to gaming enthusiasts who prioritize lag-free experience. With a 4K display and network-connected games, the GPU is expected to deliver better gaming speeds. GDDR5 is known for its responsive gaming experience for the GTX 1000 series GPU. it delivers a better bandwidth and allows smooth rendering of the graphics. GDDR6 was launched with the high-end GTX 2000 series GPUs. As a result, the gaming speed was already incredible. Along with overclocking and multichannel support, the speed can be further increased. Gaming is further enhanced as the memory supports higher resolution and network-connected games.
GDDR5 and GDDR6 – FAQs
Ans: Like any other hardware component, the GDDR5 also produces heat during operations. The temperature depends on the type of load on the GPU. During extensive load or using demanding applications, the GDDR5 memory does heat up. To avoid overheating, the memory uses air from the GPU cooler or additional heat sinks.
Ans: Considering the heavy nature of the load handled by GDDR6 RAM, it is designed to sustain higher temperatures. On average, the temperature is limited to 80 to 90 degrees Celsius to avoid performance instability. For gaming profiles, GDDR6 can sustain a maximum temperature of 100 degrees Celsius for a short time. Proper cooling and high-quality materials help achieve this limit.
Ans: GPUs are designed to work effectively up to a temperature of 80 degrees Celsius. Beyond this temperature range, the GPU experiences thermal throttling and a drop in performance. During gaming in extreme settings, the temperature can go beyond 80 degrees Celsius. To keep the temperature in control, cooling solutions are used.
Ans: The specifications of GDDR6 are much better compared to those of GDDR5. Hence, a boost in performance is achieved in the vase of GDDR6. The manufacturers of GDDR6 memory claim it has over double the data transfer speed compared to GDDR5. The channels are also doubled (DDR5 had 1 channel). GDDR6 also offers a bandwidth of more than that of GDDR5.
Conclusion
GDDR memory has become integral to the GPU over the last decades. They play an important role in boosting the graphical performance of GPUs by offering dedicated memory. This also helps reduce the system’s load, further improving the performance delivery. This article helps understand two important versions of GDDR memory: GDDR5 and GDDR6. GDDR6 is an ideal option for performance-hungry users thanks to its improved specifications. GDDR5 and GDDR5X are good options for the budget and mid-range GPUs.
