GDDR7 at 37 Gbps to enable up to 1.7 TB/s bandwidth for 384-bit cards
Samsung is preparing 37 GB/s graphics memory based on GDDR7 technology.
The upcoming 2024 ISSCC program outlines plans for high-speed memory, featuring 37 Gb/s and 35.4 Gb/s variants based on Samsung and SK Hynix’s GDDR7 specifications. Both companies intend to delve into advancements in graphics memory, utilizing the innovative PAM3 and NRZ signaling technologies.
While GDDR7 memory, with speeds reaching up to 32 Gb/s, has already been officially announced, Samsung and Hynix are pushing the boundaries further with even faster memory developments. Micron is also in the race, announcing its commitment to developing 36 Gb/s GDDR7 memory, expected to hit the market no earlier than 2026. In this competitive landscape, Samsung and Hynix are set to introduce first modules with slightly lower speeds, most likely gradually making 35 Gb/s modules available at a later stage.
Samsung & Hynix GDDR7 conferences, Source: ISSCC
Memory speeds and bandwidth
- [GDDR6/X] 256-bit @ 23 Gbps: 736 GB/s RTX 4080 SUPER
- [GDDR6] 384-bit @ 20 Gbps: 960 GB/s RX 7900 XTX
- [GDDR6/X] 384-bit @ 21 Gbps: 1.00 TB/s RTX 4090
- [GDDR6] 256-bit @ 24 Gbps: 768 GB/s
- [GDDR6] 384-bit @ 24 Gbps: 1.15 TB/s
- [GDDR7] 256-bit @ 32 Gbps: 1.00 TB/s
- [GDDR7] 384-bit @ 32 Gbps: 1.53 TB/s
- [GDDR7] 256-bit @ 37 Gbps: 1.18 TB/s
- [GDDR7] 384-bit @ 37 Gbps: 1.79 TB/s
Samsung emerged as one of the first companies to introduce GDDR6 memory with speeds reaching 24 Gb/s, a speed not yet used by any discrete desktop GPUs. The current leading GPU in the market in this category (RTX 4080 SUPER) employs 23 Gb/s memory connected to a 256-bit memory bus, while even the high-end RTX 4090 utilizes slower 21 Gb/s memory.
It’s improbable that the speeds outlined in the ISSCC program will find immediate use in the RTX 50 or RX 8000 series. Although the details and perhaps a roadmap will be unveiled at ISSCC, if Micron’s plans are any indicator into GDDR7 timeline such speeds should not be expected until the generation succeeding the upcoming one.
In a previous disclosure, Samsung highlighted GDDR7 memory, promising a 20% improvement in power efficiency and enabling a bandwidth of 1.5 TB/s. This is a notable 1.4 times faster than the 1.1 TB/s offered by GDDR6. Importantly, such speeds have not been witnessed in any RTX 40 GPU or RX 7000 card currently available in the market.
