Updated 19 October 2026.
GDDR6 is a type of memory designed to move graphics data quickly. A graphics card uses it for information such as textures and render targets. Some consoles use it as shared system memory, so comparing their memory figures directly with a PC graphics card takes care.
Capacity and bandwidth answer different questions
Capacity, measured in gigabytes, tells you how much data the memory can hold. Bandwidth, usually shown in gigabytes per second, describes its theoretical transfer rate. More capacity does not automatically mean more bandwidth, and neither figure alone predicts game performance.
Think of capacity as space on a workbench and bandwidth as how quickly you can move materials to it. A larger bench helps when the work would otherwise overflow. It does not make every other part of the job faster.
| Specification | What to look for |
|---|---|
| Memory capacity, such as 8 GB or 16 GB | Whether the game and settings fit comfortably. |
| Data rate per pin, in Gb/s | One part of the bandwidth calculation. |
| Memory bus width, in bits | The other part of that calculation. |
| Measured performance | How the complete GPU handles your workload. |
How to calculate theoretical bandwidth
For a straightforward comparison, use:
Bandwidth (GB/s) = data rate per pin (Gb/s) × bus width (bits) ÷ 8For example, 16 Gb/s × 256 bits ÷ 8 = 512 GB/s. These are illustrative numbers, not a specification for every GDDR6 card. The division converts bits to bytes; real workloads also involve caches, memory access patterns and other limits.
A faster memory chip on a narrower bus can therefore have less total bandwidth than a slower chip on a wider bus. Check the complete specification rather than comparing only the number printed next to “Gb/s.”
GDDR6, GDDR6X and GDDR7
| Type | Signal approach | What to remember |
|---|---|---|
| GDDR6 | Binary signaling, also called NRZ or PAM2. | Common graphics memory; speed varies by product. |
| GDDR6X | PAM4 signaling. | A distinct memory technology, not a setting that unlocks ordinary GDDR6. |
| GDDR7 | PAM3 signaling. | Requires suitable hardware; it is not a replacement chip upgrade for an older card. |
These differences are explained in Micron’s graphics memory overview and its GDDR6X information. The manufacturer’s GDDR7 page also explains why the newer generation needs a different controller. Published speed examples describe particular products, not a permanent maximum for every generation.
What this means for PCs and consoles
On a typical gaming PC, the graphics card’s VRAM is separate from the system RAM. Console memory arrangements can be shared between graphics and other work. The advertised total is therefore not necessarily all available to game textures.
When choosing a GPU, compare tests of the actual cards at your resolution and settings. If you already own the card, monitor its memory use and performance during a repeatable scene. High reported allocation alone does not prove you have run out of usable memory.
You cannot add VRAM in the same way you insert a desktop RAM module. Graphics memory is part of the board design, including its controller, wiring and firmware.
FAQs
Is GDDR6 the same as DDR6 system RAM?
No. GDDR graphics memory and desktop DDR memory are different product families and are not interchangeable.
Does 16 GB always beat 8 GB?
No. Extra capacity helps when a workload needs it, but GPU design, bandwidth and software also affect performance.
Can I upgrade a GDDR6 card to GDDR7?
No normal user upgrade does that. The memory generation depends on the card’s hardware design.
Does twice the bandwidth give twice the FPS?
No. Bandwidth is one resource; a game may be limited by the GPU’s other units, the CPU or software.