How to Install a Custom PS1 BIOS: A Step-by-Step Hardware Guide

Replacing the BIOS on an original PlayStation 1 allows for powerful features like Game ID reporting, region-free booting, and enhanced software compatibility. If you have a pre-flashed BIOS chip already soldered onto an adapter PCB, the hardest part—the programming—is already done. Now, it’s time to perform the "brain surgery" on your console.

Tools Required

• Soldering Iron & Solder

• Flux (Lots of it!)

• Hot air rework station (preferred) or sharp flush cutters (For remove old bios only, not for installation)

• Solder wick (braid)

• Isopropyl Alcohol (90%+) and Q-tips

Step 1: Locate the Original BIOS Chip

Open your PlayStation 1 and locate the motherboard. You are looking for IC102.

• On most models, this is a 32-pin surface-mount chip.

• On some very early models (SCPH-1001), it may be a 40-pin chip. Ensure your replacement PCB matches your motherboard's pin count.

Step 2: Remove the Factory BIOS

There are two ways to do this:

• The Professional Way: Use a hot air rework station to heat the pins evenly until the chip can be lifted off with tweezers.

• The "No-Air" Way: If you don't care about keeping the old chip, use sharp flush cutters to carefully snip the legs of each pin. Once the chip body is removed, use your iron to sweep away the remaining metal "feet."

Step 3: Clean the Pads

Apply flux to the motherboard pads and use solder wick to remove any old, crusty solder. The pads should be flat and shiny. Clean the area thoroughly with isopropyl alcohol to remove burnt flux residue.

Step 4: Align the New BIOS PCB

Place your pre-assembled BIOS adapter PCB onto the empty pads.

• Critical: Match the "Pin 1" indicator (usually a small dot or notch) on your PCB with the Pin 1 mark on the motherboard.

• Use a tiny bit of solder to "tack" down one corner pin. Check your alignment. If it's straight, tack down the opposite corner.

Step 5: Final Soldering

Apply a liberal amount of flux across the pins. Using a clean soldering iron tip, solder the remaining pins. The flux will help the solder flow onto the pads and prevent bridges.

• Note: The pads on the adapter PCB are usually larger than the original chip legs, making it easier to get a solid connection.

Step 6: Inspection and Cleanup

Check for "bridges" (solder connecting two pins that shouldn't be). If you find one, add more flux and swipe your iron across it. Once finished, clean the entire area with alcohol one last time.

Step 7: Testing

Try turn on your console, if success enter into ps1 menu(not blank), meaning your soldering success. If blank when you boot meaning its not success, please retry again.

Conclusion

Reassemble your console and power it on. If successful, you will see the classic Sony boot logo (or your custom logo), and your PS1 is now equipped with its new custom BIOS, ready for advanced features and better disc-based game handling!