Picking a CPU for a dedicated server is where most people either overspend badly or underspend and regret it three months later. The specifications are easy to find and hard to interpret, because the number that matters changes completely depending on what you are running.<\/p>\n
This is a practical guide to reading those numbers, using real configurations and prices rather than abstractions.<\/p>\n
Before looking at any CPU, work out whether your workload is limited by single thread speed or by total throughput.<\/p>\n
Single thread limited means one process has to finish a piece of work as fast as possible and cannot be split up. Game servers, most PHP applications, many database queries, and anything doing sequential logic. Adding cores does nothing for these. Clock speed and instructions per clock are what matter.<\/p>\n
Throughput limited means you have lots of independent work and want to get through as much of it as possible. Virtualisation, container hosting, video encoding, build pipelines, batch processing. Here cores matter far more than clock speed.<\/p>\n
Get this wrong and you can pay double for a CPU that performs worse on your specific job.<\/p>\n
Most hosting comparison tables, ours included, list a PassMark CPU score. It is a reasonable rough guide to total throughput, but it is a composite of many tests and it rewards core count heavily.<\/p>\n
Take two of our own configurations. The AMD EPYC 7401P scores 28,282 with 24 cores at 2 GHz, at 324 euro a month. The Intel Core i9-9900K scores 18,650 with 8 cores at 3.6 GHz, at 91 euro a month.<\/p>\n
By PassMark the EPYC looks 50 percent better. For a Minecraft server the i9-9900K would beat it comfortably, because what that workload needs is one core running fast, and 3.6 GHz beats 2 GHz. The EPYC is the better machine for running twenty virtual machines. It is the worse machine for running one game server, at three and a half times the price.<\/p>\n
Read the composite score for throughput work. For single thread work, look at the clock.<\/p>\n
The i9-9900K comes up often enough in search queries that it deserves a section of its own. It is an eight core, sixteen thread part running at 3.6 GHz base, and on our Intel server range<\/a> it is configured with 128 GB DDR4 and two 1 TB NVMe SSDs at 91 euro a month.<\/p>\n It sits in a useful spot. The cheaper Intel options in our lineup, the Xeon E3-1275v5 at 59 euro and the Core i7-6700 at 60 euro, are four core parts scoring around 8,000. The i9-9900K roughly doubles that while keeping a high clock, and the 128 GB of RAM is generous for the price.<\/p>\n It suits game server hosting, small to medium virtualisation where you want both decent clocks and some core count, application servers that are memory hungry, and general purpose workloads where you do not want to commit to either extreme.<\/p>\n