Exploring PCIE 4.0 trends
Exploring PCIE 4.0 trends
PCIE 3.0 supports up to 16 Gbits bandwidth, while PCIE 4.0 offers 32 Gbits. The RTX 3080 has a VRAM speed of 19 Gbits per second. Based on Nvidia's specs, it would indeed be limited to about 3 Gbits per second in PCIe 3.0 due to the bandwidth constraints.
I'd say yes and no... Technically the card won't get the absolute top speed of memory transfer... but at the same time, I highly doubt there's a single game out there right now aside from tech demos and benchmarks, that can actually fully saturate the bandwidth of PCIe 3.0, so you probably aren't even going to notice the difference. It's like worrying if your new car can break 150mph, when you're only able to drive it on the highway at 65-80mph. granted, I'm not an expert by any stretch... that's just the general advice I've seen around lately...
I appreciate the clarification. My example doesn’t fit your needs since I can reach speeds up to 150 mph. That means we probably don’t need to focus on PCIe 4.0 right now.
The bandwidth of the RTX 3080 is not specified in the available specs. The only detail provided is 19GBITS.
We also discover the performance reduction owners might face when using these cards with PCIe 3.0 rather than PCIe 4.0. “System performance is affected by numerous elements and the effect differs across applications,” explained NVIDIA’s Seth Schneider. “The decrease is usually under a few percent when switching from x16 PCIe 4.0 to x16 PCIe 3.0. CPU choice often plays a bigger role in performance. We’re eager for upcoming platforms that can fully utilize Gen4 features for possible gains.” If you intend to continue using PCIe 3.0 in the near term, major performance drops seem unlikely. For those considering an RTX 30-series card, the AMA provides extensive coverage worth reviewing. We’ll keep gaining insights about the RTX 30-series in the coming days and weeks—stay updated!
I don’t have the precise maximum bandwidth numbers for those GPUs. Nvidia mentioned that PCIe 4.0 isn’t necessary for them, noting a modest speed boost from PCIe 3 to 4, but emphasized that a stronger gaming CPU matters more. They actually tested with an i9 instead of an AMD CPU with PCIe 4, which performed worse in games.
what bandwidth refers to? it relates to your PCIe connection. The top speed you need depends on what you're doing—different tasks need different amounts. For gaming, you'd likely focus on the latest options rather than older standards like PCIe 3.0. Recent reviews suggest that faster CPUs have more impact than PCIe version, so PCIe 3.0 might not be as critical now, though it can still work well if you're concerned about performance differences between PCIe 3.0 and 4.0 cards.
The requirement for memory bandwidth is unrelated to PCIe bandwidth needs. That's the conclusion.