Crucial

Available in 1.9TB, 2TB, 4TB and 5TB capacities these SATA III 6Gb/s SSDs may no longer be the fastest around thanks to emerging PCIe SSDs, but they're the most cost-effective and are still easily fast enough for most users. You'll need a spare SATA 6Gb/s port to get the most from them, and a 2.5" capable drive bay - an adaptor may need to be bought, but most cases have at least one. These drives are the highest capacity ones available, suitable for holding an operating system, as well as numerous programs and a healthy collection of media and games.

Available in 120, 128, 240, 250, 256, 275 and 480GB capacities these SATA III 6Gb/s SSDs may no longer be the fastest around thanks to emerging PCIe SSDs, but they're the most cost-effective and are still easily fast enough for most users. You'll need a spare SATA 6Gb/s port to get the most from them, and a 2.5" capable drive bay - an adaptor may need to be bought, but most cases have at least one. These drives are suitable for holding an operating system, as well as numerous programs and a healthy collection of media and games.

M.2 replaced the older mSATA standard. Available in 120, 128, 240, 256, 480, 500 and 512GB sizes the M.2 SSD connects to your device via an M.2 socket using the newer PCI Express NVMe (Non-Volatile Memory Express) controller variant designed to fully utilise the capability of high-speed PCI Express storage devices to perform many I/O (in/out) operations in parallel. These SSD's can achieve read speeds in excess of 3000MB/s and write speeds over 2000MB/s making them the fastest available.

While the M.2 connector can be used for PCIe SSDs, the ones here are SATA 6Gb/s only, so the benefits over standard 2.5" SATA drives are to do with space-saving, not speed. Available in 120, 240, 256, 480, 500 and 512GB sizes they're perfect for small form factor systems and laptops, but make sure your M.2 slot works with SATA devices, and that it supports the SSD's size, both in length (2280 means 80mm long) and thickness.

Available in 500, 512, 525, 960GB and 1TB capacities these SATA III 6Gb/s SSDs may no longer be the fastest around thanks to emerging PCIe SSDs, but they're the most cost-effective and are still easily fast enough for most users. You'll need a spare SATA 6Gb/s port to get the most from them, and a 2.5" capable drive bay - an adaptor may need to be bought, but most cases have at least one. These drives are suitable for holding an operating system, as well as numerous programs and a healthy collection of media and games.

While the M.2 connector can be used for PCIe SSDs, the ones here are SATA 6Gb/s only, so the benefits over standard 2.5" SATA drives are to do with space-saving, not speed. Available in 1TB and 2TB sizes they're perfect for small form factor systems and laptops, but make sure your M.2 slot works with SATA devices, and that it supports the SSD's size, both in length (2280 means 80mm long) and thickness.

M.2 replaced the older mSATA standard. Available in 960GB, 1TB, 2TB, 4TB & 8TB sizes the M.2 SSD Connects to your device via an M.2 Socket using the newer PCI Express NVMe (Non-Volatile Memory Express) controller variant designed to fully utilize the capability of high-speed PCI Express storage devices to perform many I/O (in/out) operations in parallel. These SSD's can achieve Read speeds in Excess of 3000MB/s and Write speeds over 2000MB/s making them the fastest available.

The Mac Memory SODIMMs allow users to maximize memory bandwidth and minimize performance bottlenecks to deliver a superior user experience. Built to Corsair’s legendary quality and reliability standards, each module is tested to ensure maximum compatibility. Each Mac Memory module is individually tested and certified to be compatible with Apple products.

DDR3 SDRAM is an evolution of DDR2 SDRAM. Designed for todays systems which support DDR3, the primary benefit of DDR3 being the ability to transfer data at a much higher rate than DDR2 due to the higher clock rate. This allows you to take advantage of the high speeds offered by todays CPU's. These memory modules are available in single, dual and quad packs, and have a clock speed of 1600Mhz.
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SODIMM memory is smaller than standard modules, and is used in laptops and mini-PCs. As long as you can access your system's memory slots, you can upgrade it. The kits here come in a range of speeds and capacities, so make sure your system is compatible with the memory you choose.

DDR4 SDRAM is the fastest and most efficient consumer memory available. It's compatible with Intel's Broadwell-E which run in quad-channel and Kaby Lake & Skylake CPUs which run in dual-channelmodes. It is also compatible with AMD's latest RYZEN CPUs running in a dual-channel configuration. The modules found here are designed for Intel Kaby Lake, Intel Skylake & AMD RYZEN, so they're sold in matching kits of two modules for best performance or single modules for a cheap upgrade. These are the mid-range kits, with a speed of 2,400MHz.

Available as regular DIMMs or SO-DIMMs for micro-servers, these DDR3 modules are designed for servers and are engineered and clocked to provide rock solid stability 24/7. ECC (error correcting code) modules are immune to errors, while registered/buffered sticks reduce memory controller load and ensure additional stability when using many modules together. Motherboards need to support ECC and registered memory for these features to work.

DDR4 server memory brings maximum speed and efficiency to Intel's quad-channel Xeon E5 and six-channel Xeon Scalable platform and AMD's eight-channel EPYC platform.

Server memory is designed to have rock solid stability 24/7. ECC (error correcting code) modules are immune to errors, while registered/buffered sticks reduce memory controller load and ensure additional stability when using many modules together. Motherboards need to support ECC and registered memory for these features to work. These particular modules are rated up to 2400MHz.

External SSDs are ideal for users looking for lightweight, portable and speedy storage. Their pocket-friendly enclosures are significantly smaller and lighter than external hard drives, and with no moving parts they're also silent, more robust and less prone to physical shock damage. They use the USB 3 interface, which is 10 times faster than and backwards compatible with USB 2.