Editing Removed

===i.LINK port (SCPH-390xx and earlier)===
i.LINK port (based on FireWire 400/IEEE1394 interface) was removed in SCPH-500xx and later.

i.LINK port was mostly used for creating multiplayer network involving multiple PS2 units.

===Expansion Bay (SCPH-3000x to SCPH-500xx/5500x)===
Expansion Bay was last time available in SCPH-500xx/5500x, so in last "FAT" model.

Removing the Expansion Bay disallowed games like Final Fantasy XI (11), or software like Linux to run on slim units.

===ATA port (SCPH-700xx and earlier)===
ATA port was in theory removed with removing Expansion Bay.

But in SCPH-700xx (first slim model) Sony leaved hardware, and ATA pins required to connect HDD on motherboard.

So ATA port was really removed in SCPH-750xx and later.

===IOP (aka MIPS R3000A/PS1 CPU) (SCPH-700xx and earlier) ===
Used by PS2 as the IOP or as the CPU used to run PS1 games (is the same CPU that PS1 had).

Since SCPH-750xx units, IOP was replaced by PowerPC CPU that emulates IOP.

This resulted in some minor, or major compatibility issues for PS1/PS2 game titles.

===System and DVD player update ability (SCPH-900xx with BIOS v2.20 and earlier)===
In BIOS v2.30 and v2.50, Sony removed support for system update via memory card to block FMCB exploit.

The system update exploit used this ability to inject own code into console RAM, and allow to run custom code that way.

It also removed support for DVD player update via memory card.

BIOS v2.30 can be found in majority of SCPH-900xx units, while BIOS v2.50 can only found in Europe-only KDL-22PX300 Bravia units.

===SPC970-based MechaCon (SCPH-390xx and earlier)===
It was replaced with Dragon MechaCon found in SCPH-500xx and later.

===Component/RGB video output (SCPH-900xx with BIOS v2.30 and earlier)===
This feature was removed in BIOS v2.50 found in Europe-only KDL-22PX300 Bravia units.

===ProtoKernel BIOS (SCPH-10000/15000) ===
This BIOS was replaced with the final kernel BIOS found in SCPH-18000 and later.

===Static RSOD until pressing RESET button (SCPH-18000 and earlier)===
Press RESET button to get rid of the static RSOD, this odd behavior was fixed in SCPH-3000x and later.

===PCMCIA port (SCPH-18000 and earlier)===
This feature was removed in SCPH-3000x and later.

===Buggy DVD Player 1.00J (SCPH-10000 with BIOS v1.00)===
This update was blocked in SCPH-10000/15000 with BIOS v1.01 and later.