SSD

speed of a PCIe 4.0 NVMe SSD in a PCIe 3.0 Motherboard Slot?

# Interface

# Clone SSD on Linux ⮺

NOTE: both disk must be unmounted during the copy
Otherwise you may end up with error on partition (eg the /boot/efi)

$ lsblk
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
sda           8:0    0 931,5G  0 disk 
└─sda1        8:1    0 931,5G  0 part /media/yves/USB STICK
nvme0n1     259:0    0 476,9G  0 disk 
├─nvme0n1p1 259:1    0   100M  0 part /boot/efi
...
512110190592 bytes (512 GB, 477 GiB) copied, 1184,7 s, 432 MB/s
$ sudo dd if=/dev/nvme0n1 of=/dev/sda bs=64M status=progress
$ sync

# Extend partition

Then gparted can be used to move & resize existing partition.

# Convert MBR to GPT ⮺

an MBR-partitioned (standard) drive cannot be > 2To. You need GPT.

Non destructrive process

$ sudo gdisk /dev/sdX
# then press w to write converted partition
w

# PC-Hardware 📟

Model	Capacity	Interface	Price / Year	Location / Source
fanxiang SSD NVMe S910 Pro	4 To / 14G B/s	🖴 NVMe PCIe 5.0 x4	330€ (2025)	Mac Classic
Fikwot FN950	1 To / 4.8 GB/s	🖴 NVMe	—	huawei matebook 14
🔧 Lexar NM610 Pro	1 To / 3.3 GB/s	🖴 NVMe	—	—
🔧 WD SN730	0.5 To / 3.4 GB/s	🖴 NVMe	OEM (2020)	♻️ huawei matebook 14
🔧 WD Green	240 Go / 0.5 GB/s	🖴 SATA	36€ (2020)	♻️ lab 2020

🔧: Spare
🖴: M.2 2280
♻️: from

# Performance

# SSD performance over USB ⮺

Notes - pcie gen 5.0 not recognized by a usb 3.1 nvme adapter? - this is expected…

Interface	Real-world speed	Relative speed vs PCIe 3.0
PCIe 3.0 x4 NVMe	3,000–3,500 MB/s	100%
USB 3.1 Gen 2 NVMe	700–1,050 MB/s	20–30%
USB 3.1 Gen 1 NVMe	350–500 MB/s	10–15%
USB 2.0 NVMe	30–40 MB/s	1%

# PCI-Express Speeds

Version	x1 Bandwidth	x2 Bandwidth	x4 Bandwidth	x8 Bandwidth	x16 Bandwidth
PCIe 1.0	250 MB/s	500 MB/s	750 MB/s	2 GB/s	4 GB/s
PCIe 2.0	500 MB/s	1000 MB/s	2 GB/s	4 GB/s	8 GB/s
PCIe 3.0	1 GB/s	2 GB/s	4 GB/s	8 GB/s	16 GB/s
PCIe 4.0	2 GB/s	4 GB/s	8 GB/s	16 GB/s	32 GB/s
PCIe 5.0	4 GB/s	8 GB/s	16 GB/s	32 GB/s	63 GB/s
PCIe 6.0	8 GB/s	15 GB/s	30 GB/s	61 GB/s	121 GB/s
PCIe 7.0	15 GB/s	30 GB/s	61 GB/s	121 GB/s	242 GB/s

# SSD Sticker

some acts as heat spreader

Written on November 28, 2025, Last update on January 2, 2026

pc-hardware disk storage