Practical fixes for what most often makes a Windows PC slower than its hardware: slow start-up, short freezes, a busy drive, memory, graphics settings, AI models running on the processor and worn batteries. Each starts with what you can fix for free, and each works without Bottleneck — though Bottleneck will tell you which of them apply to your machine.
Choosing parts, or wondering about a pair you have? The bottleneck calculator shows whether a processor would hold a graphics card back at 1080p, 1440p and 4K, and CPU and GPU pairings has a page for each common pair. The GPU comparison chart ranks every graphics card, with the best processor for each, and the CPU comparison chart ranks every processor, with the best graphics card for each, and the PSU calculator sizes the power supply for a pair. Can my PC run it? checks a PC against the requirements of popular games, and Can my PC run AI? lists the open AI models a PC can run itself, and how fast each one writes. Two quick checks in the browser: which graphics card you have, and what refresh rate your monitor runs at.
A slow PC usually has one or two causes that cost nothing to fix. What to check first, in order: background programs, startup apps, storage, memory, power and heat.
Windows times every start and records what made it slower. How to read that record, and what to do about each cause.
Short freezes usually mean memory ran out, the drive could not keep up or the processor was flat out. How to tell which, and fix it.
How to find which program keeps the drive busy, the usual causes in Windows 11 and 10, and the fixes that last.
Blue screens, sudden shutdowns, freezes and games closing to the desktop: where Windows records each, and what each kind usually means.
A hardware error the PC could not correct: how to find which part reported it, and the settings that usually cause it.
When the screen goes black and the graphics driver resets, and when it ends in a blue screen: drivers, tuning, power and heat.
How to read the restart record — a blue screen, the power button, sleep or nothing at all — and what to check when it shuts off while gaming.
A processor core stopped responding: overclocks, undervolts, an old BIOS and Intel 13th and 14th gen.
How to test the memory, what to try with XMP or EXPO, and when a driver is to blame.
A driver kept the processor busy too long: how to find which, and the storage, graphics and Bluetooth drivers that usually do it.
What different kinds of use need, how to check in Task Manager whether your PC runs out, and what to know before adding more.
Most desktop memory starts at a slower default speed until XMP or EXPO is switched on in the firmware. How to check the speed it really runs at, and fix it in a minute.
One memory stick, or two in the wrong slots, halves memory bandwidth. How to check which you have, and move a stick to fix it.
How to tell whether the processor or the graphics card sets the pace, why total CPU usage misleads, and what to rule out before buying anything.
A graphics card at 50–70% while a game runs slower than you want is waiting for something. The causes in the order worth checking.
What it does, what it needs, how to check it on NVIDIA, AMD and Intel cards, and how to switch it on in the firmware.
What the setting does, why DLSS Frame Generation needs it, and where to find it in Windows 11 and 10.
A 144 Hz monitor can run at 60 Hz for years without anyone noticing. How to check it in Windows 11 and 10, and what to do when the faster rate is not offered.
A model partly on the processor writes several times more slowly, and Ollama does not say. How to see where yours runs, and the fixes in the order worth trying.
GPU Offload, the engine and the context length: the settings that put a model on the graphics card, and how to check where it runs.
What the names mean, how much memory each takes and how much quality it keeps, and which to choose for your graphics card.
Both are free and run the same models with the same engine. How they differ, which is faster, and which suits what you want to do.
The difference between dedicated and shared GPU memory in Task Manager, why spilling into shared memory is slow, and what helps.
Also: see what tokens per second look like, and the best GPU for local AI, with every card’s speed.
A nearly full drive, TRIM switched off, or an NVMe drive in a slow slot: how to check each one in Windows.
Drives usually warn before they fail. How to read their health in Windows, what the numbers mean, and what to do next.
Windows records how much charge the battery holds compared with when it was new. How to read it in two minutes, and what the numbers mean.
Which tests find which problems, how long to run them, which temperatures are normal, and what to do when a test fails.
Games now warn about it. What it is, how to check your PC for Intel’s fix in a minute, and how to install it with a BIOS update.
Windows 10 support has ended. Which PCs can move to Windows 11, the two firmware settings that fail machines that are fine, and how to plan the rest.
Bottleneck scans a PC in a few minutes and names every problem it finds, ranked by what it is costing you. The free version has no time limit and needs no account.
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