Gigabyte per second to Gigabit per second

CPUs constantly shuttle data between RAM and their caches. DDR5-6000 provides about 96 GB/s of bandwidth in dual-channel mode. In games, insufficient RAM bandwidth causes frame drops during complex scenes. In productivity tasks like video encoding, it directly limits how fast the CPU can process data.

Thunderbolt 4 runs at 40 Gbps, which is 5 GB/s. Thunderbolt 5, released in 2024, doubles this to 80 Gbps (10 GB/s) with a burst mode up to 120 Gbps (15 GB/s). This is fast enough to run an external NVMe SSD at near-internal speeds.

Both, depending on generation. A PCIe 3.0 ×4 interface caps at ~3.5 GB/s, bottlenecking modern NAND. PCIe 4.0 ×4 raises this to ~7 GB/s, and PCIe 5.0 ×4 to ~14 GB/s. The drive's NAND flash and controller also have limits — the fastest SSDs and the fastest interfaces are in a constant leapfrog.

GPUs use wide memory buses (256–384 bits) with very fast HBM or GDDR6X memory running at high clock speeds. An RTX 4090 has a 384-bit bus with GDDR6X at 21 Gbps per pin, totalling 1,008 GB/s. HBM3 in data center GPUs achieves 3,000+ GB/s through stacked memory with 4096-bit buses.

At multi-GB/s rates, CPU processing speed, software efficiency, and thermal throttling become bottlenecks. A 14 GB/s PCIe 5.0 SSD can deliver data faster than most applications can consume it. Decompression, parsing, and memory allocation in software often cannot keep up with raw storage bandwidth.

For most households, no. A family of four streaming 4K, gaming, and video-calling simultaneously uses about 100–150 Mbps. Gigabit becomes worthwhile if you regularly transfer large files, run a home server, or have 15+ connected devices all active at once. The real benefit is future-proofing.

Dedicated bandwidth means your 1 Gbps line is yours alone — common in business fiber (leased lines). Residential fiber is shared: a 10 Gbps trunk splits across 32–128 homes via a passive optical splitter (GPON). During peak evening hours, your "gigabit" plan might deliver 300–600 Mbps because neighbors are all streaming. This is why business fiber costs 5–10× more for the same headline speed — you are paying for a guarantee, not just capacity.

As of 2026, several ISPs offer 10 Gbps residential plans in select cities — Google Fiber, AT&T, and some European providers. South Korea and Japan have had multi-gigabit home connections since the early 2020s. The bottleneck is usually the home network equipment, not the ISP connection.

Data centers connect racks of servers with 25–100 Gbps links to handle millions of simultaneous user requests. A single popular website might serve hundreds of Gbps of traffic during peak hours. Spine-leaf network architectures aggregate these links to provide non-blocking Tbps-class switching capacity.

A traditional spinning hard drive writes at about 1–1.5 Gbps (125–180 MB/s), so it can just barely keep up with a 1 Gbps connection. An NVMe SSD at 3–7 Gbps handles it easily. If you have gigabit internet but an old HDD, your disk is the bottleneck, not your connection.