Intel Core i9-9900X Processor

The Intel Core i9-9900X Processor — 10 cores and 20 threads, 3.5 GHz base rising to 4.4 GHz with Turbo Boost, 19.25 MB Intel Smart Cache, 165 W processor base power, LGA2066. Supplied from stock with a 1-year warranty.

Ten Cascade Lake cores at 3.50 GHz

The i9-9900X is the ten-core Cascade Lake-X i9: ten cores with Hyper-Threading at 3.50 GHz with a 4.40 GHz Turbo, 19.25 MB of cache and a 165 W envelope, launched Q4 2018. The higher base clock and larger cache than the Skylake-X ten-core made it the balanced choice of the refresh.

It carries the full HEDT feature set — quad-channel DDR4-2666, 44 PCIe 3.0 lanes, two AVX-512 FMA units per core and an unlocked multiplier — on a socket that spans six processor generations.

Technical specifications

Instruction set extensions: Intel SSE4.1, SSE4.2, AVX and AVX2, plus AVX-512 with two 512-bit FMA units. Security and virtualisation: AES-NI, Intel VT-x with EPT and VT-d, Intel Boot Guard.

Which systems take this processor

Anything on the LGA2066 socket with an Intel X299 chipset. This is the HEDT (high-end desktop) platform: quad-channel memory, up to 44 PCIe 3.0 lanes from the CPU and physically larger boards than the mainstream LGA1151 / LGA1200 lines.

Workstations and compute boxes — ASUS Prime X299 / Pro X299, MSI X299 RAIDER, Gigabyte X299 AORUS. Four memory channels and the 44-lane pool suit NVMe arrays, GPU compute and 10 GbE add-in cards that starve on mainstream sockets.

Upgrade path — an X299 board also accepts 6th to 10th Generation Core X processors up to 18 cores, so a build started with this part can be scaled up later without changing the platform.

One caveat: LGA2066 boards and coolers are not interchangeable with mainstream sockets — the socket, the cooler mounting and the memory layout are all different. Make sure your chassis supports an ATX or E-ATX board before ordering. Tell us the board model when you enquire and we will confirm.

How it compares across the i9 line

The 9940X adds four more cores at slightly lower base clock, and the twelve-core 10920X is the later refresh of that class on the same board.

How each processor is tested before it ships

1. Visual inspection of the integrated heat spreader, substrate and contact pads; the sSpec laser marking (SREZ7 on our i9-9900X stock) is verified against the Intel specification sheet.
2. Burn-in on a matched diagnostic board with four matched memory modules (all four channels must be populated to reach the rated bandwidth).
3. All populated memory channels and the primary PCIe lanes are validated, then the processor is identified in the BIOS and in the operating system.
4. A sustained multi-threaded load test at full core count, with the clock and thermal readings recorded.
5. Thermal paste cleaned off, final inspection, then packaging in an anti-static tray with foam — which is how it arrives to you.

Warranty and lead time

Every processor is covered by a 1-year warranty against defects in workmanship and function. If a part fails within the period we replace it or refund it, and we cover return shipping on a verified fault. Stock is held in our own warehouse and normally dispatches within three to seven working days; tracking is issued at dispatch.

Purchasing and volume enquiries

The minimum order quantity for this processor is 2 units. Price is quotation-based rather than listed, because CPU pricing moves with each incoming batch — send us the quantity you need and we will come back with a firm quote and the current lead time. Larger quantities ship from the same production batch so the sSpec and the stepping stay consistent across your order.