Gibibyte per second to Mebibyte per second

GPU memory is addressed in binary (power-of-2 bus widths like 256-bit or 384-bit), so binary units naturally describe the actual hardware capability. Some vendors use GiB/s to be precise, while marketing materials prefer the larger-sounding GB/s number. The RTX 4090's 1,008 GiB/s is 1,082 GB/s — the latter sounds faster.

DDR5-6000 in dual-channel mode provides about 93 GiB/s (100 GB/s). Quad-channel DDR5 on workstation platforms doubles this to ~186 GiB/s. The actual usable bandwidth depends on memory access patterns — random access achieves far less than sequential streaming.

Memory bandwidth (50–100+ GiB/s for DDR5) measures how fast the CPU can read/write RAM. Storage bandwidth (3–14 GiB/s for NVMe SSDs) measures persistent data transfer. Memory is 10–30× faster because DRAM has nanosecond latency while NAND flash has microsecond latency. They serve different roles in the data hierarchy.

Yes. For memory bandwidth, run a STREAM benchmark (available for Linux and Windows). For storage, use fio or CrystalDiskMark. GPU memory bandwidth can be tested with gpu-burn or vendor-provided tools. All will report in either GiB/s or GB/s depending on the tool — check which one.

Electrical signalling on copper traces maxes out around 112 Gbps (about 13 GiB/s) per lane with current technology. Beyond that, optics take over — silicon photonics interconnects can push individual channels to 200+ Gbps. The physical speed of light in fiber is not the limit; it is the modulation and detection electronics.

dd uses binary units because Linux filesystems work in binary block sizes (4 KiB, etc.). Drive manufacturers use decimal MB/s because it makes speeds look about 5% higher and aligns with their decimal capacity marketing. A "550 MB/s" SSD shows roughly 524 MiB/s in dd.

Run "dd if=/dev/zero of=testfile bs=1M count=1024 oflag=direct" and it will report write speed in MiB/s. For read speed, use "dd if=testfile of=/dev/null bs=1M". The oflag=direct flag bypasses filesystem cache to measure actual disk performance.

No — 550 MiB/s is about 577 MB/s, and 550 MB/s is about 524 MiB/s. The ~5% difference means an SSD advertised at 550 MB/s will show around 524 MiB/s in Linux tools. It is not a defect or false advertising, just different unit systems measuring the same physical speed.

A RAID 0 stripe of two SATA SSDs gives roughly 1,000–1,100 MiB/s sequential reads. Four NVMe SSDs in RAID 0 can hit 12,000–14,000 MiB/s. RAID 5/6 arrays sacrifice some write speed for redundancy — expect 70–90% of raw stripe performance on writes.

Sequential reads let the drive stream data from contiguous locations, maximising throughput. Random I/O forces the controller to seek different addresses, adding latency per operation. An NVMe SSD might do 7,000 MiB/s sequential but only 50–80 MiB/s random (at 4 KiB block size), because the bottleneck shifts from bandwidth to IOPS.