good guides for replacing a power supply?

Here are three reliable written guides that walk you through PSU replacement clearly:

• PC Build Advisor – Power Supply Installation Guide
  A detailed walkthrough covering removal, installation, and safety precautions. Includes photos and a checklist of connections.
  https://www.pcbuildadvisor.com/pc-power-...
• TechBloat – Step‑by‑Step PSU Replacement
  Focuses on common pitfalls (like mixing modular cables between PSUs) and troubleshooting if your PC doesn’t power on after the swap.
  https://www.techbloat.com/how-to-replace...
• XDA Developers – PSU Replacement Guide
  Offers practical advice on cable routing, securing the PSU, and ensuring all connectors (24‑pin, CPU 8‑pin, PCIe, SATA) are properly seated.
• https://www.xda-developers.com/how-chang...

When choosing a PSU, a couple of points are worth keeping in mind:

• Modular design: Modular PSUs are easier to work with since you only plug in the cables you need, which helps with airflow and cable management—especially in smaller cases. The trade‑off is that connectors must be seated properly, otherwise you risk issues like burnt pins. As long as the PSU isn’t obsolete and supports the current standards (ATX, PCIe, etc.), modular units remain a good option for future builds.
• Efficiency certification: Look for an 80 Plus certified PSU (Bronze, Gold, or higher). This ensures better efficiency, less wasted power as heat, and generally higher build quality. Over the long run, it’s worth the investment.
• Manufacturer reputation: Stick with reputable brands such as Seasonic, Corsair, Cooler Master, etc.
  A reliable PSU protects the rest of your components and saves you headaches down the line.

In short: modular units are convenient if you handle them carefully, and pairing that with an 80 Plus certified PSU from a trusted manufacturer gives you a solid, future‑proof choice.