Why a business computer becomes slow, and what actually fixes it

Open Task Manager before you do anything else

Everything else here is guesswork until you have looked. On Windows press Ctrl+Shift+Esc; on a Mac open Activity Monitor. Leave it on the Performance tab for a minute while the machine is behaving badly.

1. 1Memory above 85% with little open means not enough RAM, or something is leaking it.
2. 2Disk pinned at 100% means a failing drive, a background sync, or an antivirus scan.
3. 3High CPU with an unfamiliar process: look that process up before killing it.
4. 4Everything low but the machine still feels slow usually means heat. See below.

Disk space is the one people dismiss

A drive with under about 10% free does not just fail to save files, it slows the whole system, because the operating system needs working room. We have seen machines written off as too old come back to life from deleting 40 GB.

1. 1Check free space on the system drive. Under 10% is a problem; under 5% is the cause.
2. 2Empty the recycle bin, which people forget is still occupying the disk.
3. 3Look at the Downloads folder. On a two-year-old work machine it is routinely tens of gigabytes.
4. 4Check OneDrive settings: "always keep on this device" quietly pulls entire libraries onto a laptop.

Startup programs, and why it is only slow in the morning

If it is slow for the first ten minutes and fine afterwards, you are watching startup programs compete. Every installed application wants to launch at boot, and nobody ever removes one.

1. 1Task Manager, Startup tab. Sort by startup impact.
2. 2Disable anything with high impact that is not needed at boot. Chat and update helpers are usually safe.
3. 3Do not disable anything security-related, and do not disable something you cannot identify.
4. 4Restart and time it again, so you know whether it actually helped.

Heat, and the quiet slowdown

A computer that is too hot deliberately slows itself to avoid damage. It is doing the right thing. The symptom is a machine that starts fine and degrades over an hour, often with louder fans. The cause is nearly always dust, or a laptop sitting on fabric with its vents underneath.

1. 1Check the machine is on a hard surface with its vents clear.
2. 2Listen: constant loud fans mean it is fighting heat.
3. 3Have desktop and laptop vents cleaned out. That is physical work, so it is not something we can do remotely.

When it really is the drive

An old spinning hard drive in a machine that otherwise works is the one case where replacement is genuinely worth it. Moving to an SSD changes a slow machine more than anything else you can buy.

A drive that is failing is a different situation, and urgent. Clicking noises, files that will not open, or freezes needing a hard power-off mean back up now and worry about speed afterwards.