no need to open and modify your PS2,
you just need swapmagic 3.6 and up,
here a small guide how it works:
Is there a way to dump a bios without modding a ps2(whatever that means)
i can describe it noob-friendlier if you want.
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My System: C2D E6700 @3.4ghz | Asus P5W DH Deluxe | 4GB DDR2 800 | eVGA Geforce GTX 260 55nm SC-Edition
Tutorial: Hardware Antialiasing in PCSX2 (DX9 only)