Most “PC optimization” software is either useless or actively harmful. Registry cleaners, RAM boosters, and one-click speed-up tools are marketing fiction — they don’t work and some install malware. This list contains only tools that produce measurable, verifiable results.
System Monitoring and Benchmarking
HWiNFO64
HWiNFO64 is the gold standard for hardware monitoring. It reads data directly from sensors on your CPU, GPU, motherboard, and drives — temperatures, voltages, clock speeds, fan RPM, power draw. The summary view is overwhelming at first; use the sensor-only mode and pin what matters to your taskbar via the tray icons.
Best for: Diagnosing thermal throttling, monitoring overclocks, catching failing hardware.
Download from hwinfo.com. The portable version needs no installation.
CPU-Z and GPU-Z
Two separate tools, both from CPUID/TechPowerUp. CPU-Z reads your CPU specs, memory SPD data (actual XMP profile speeds and timings), and motherboard details. GPU-Z does the same for your graphics card — core clock, memory clock, VRAM type, BIOS version.
Use these before any overclock to establish a baseline and confirm your hardware is identified correctly.
CrystalDiskMark
The standard tool for measuring storage throughput. Run the 1GiB test for a reliable result. Sequential read/write tells you bandwidth; the random 4K numbers (especially at low queue depth) tell you how the drive handles real-world workloads.
Compare your results against the manufacturer’s rated specs. A significant drop in sequential speeds on an SSD often indicates the drive is in its SLC cache, running hot, or failing.
System Cleanup
BleachBit
Open-source Windows and Linux cleaner. Unlike CCleaner (which has had multiple shady incidents including a malware compromise in 2017), BleachBit is transparent about what it deletes and doesn’t phone home. It cleans browser caches, temp files, Windows Update leftovers, and log files.
What to clean: Temp files, browser caches, Windows log files. What to skip: Registry cleaning — it’s useless and occasionally breaks things.
TreeSize Free
Windows doesn’t make it easy to find what’s eating your drive space. TreeSize scans your filesystem and displays a sorted tree of space usage. Useful for finding forgotten game installations, old backups, and bloated application caches.
Memory and Stability Testing
MemTest86
The definitive RAM stability tester. Boots from a USB drive independently of Windows and runs low-level memory tests. If you’ve overclocked your RAM or are experiencing random crashes or BSODs, run at least one full pass (can take 30–60 minutes depending on RAM size).
One pass is a sanity check. Four passes gives you reasonable confidence. A single error means your RAM configuration is unstable.
Prime95 (Blend test)
Used to stress-test CPU stability. The Blend test exercises both the CPU and RAM simultaneously, making it the most thorough general stability check. Run for 30 minutes after any CPU overclock or voltage change. If it crashes or throws errors, the overclock isn’t stable.
Don’t use Small FFT for extended periods — it generates unrealistic heat loads that can damage air-cooled systems running aggressive curves.
Network Diagnostics
WinMTR
Combines traceroute and ping into a continuous real-time view. Shows packet loss and latency at every hop between your PC and a destination. Invaluable for diagnosing whether lag spikes are at your router, your ISP, or further upstream.
Run it pointed at your game server or a public IP (e.g., 8.8.8.8) during a problem period and export the result when filing a support ticket with your ISP.
What not to install
Avoid anything that promises to:
- “Speed up your RAM” or “optimize memory”
- Clean your registry for performance gains
- Automatically update all your drivers (these often install wrong drivers)
- Give you a “PC health score”
These tools exist to upsell you a paid subscription, not to improve your system.
The one-line summary
HWiNFO64 + CrystalDiskMark + MemTest86 covers monitoring, storage health, and RAM stability. That’s 90% of what most users need. Everything else on this list is a bonus.