For me, It don't depend of configuration at 100%.
I follow this emulator since many years (and many computers) and it s always the same. Somes games will works at 80%, and only 90% 5 years later (with better machine) and other are incredibly slow even with better machine.
Don't take care at their compatibility list, it s a joke. For them a game at 20fps, full of glitch is a game playable if you can see the end game.
If you want to try a game, just type "name of game pcsx2" on youtube, you will have a video and the configuration used for this result.
The configuration is special too, each game have its own configuration (so hard to use in a front end).
ATM my game machine is an amd x4 740 with an old 9800 GTX ,4 M ram, and for exemple :
Shadow of collossus (The better game of PS2, since 5 years, peoples try to make this game working at 100%, some of them have made special pluggins just for this game) is playable, without glitch but with some slow-down, (in the ps2 too there is slow-down ^^ in this game). Even on my principal computer (6 month old) I can't play at this game at 100% speed.
Haunting ground work at 99%, just 1 / 2 glitchs in somes reflects on water.
Loney tune Trace work at 100 % but less fast than the original.
Sonic Heros a multiplayer sonic work at 100%
Ratchet and clank 3 Work at 100 %, full speed, but impossible to play because of graphics glitchs.
Champion of norrah Not working in hardware mode so too slow ^^
No logic in that, the better way is too see video on youtube to make an opinion. But now pcsx2 is open source so I think the progress will be faster.
It s really a good emulator, no bug, no crash, no problem, easily configurable, with lot of possibilities, It s really easy to change option to see the difference, or find help on the web. Rom are easy to find too.
But I hate their team ^^.
GT3 full speed
http://www.youtube.com/watch?v=-Mb5Gfa6rdc but on a E8400 4.5Ghz (dual core, but I m not sure it s the real full speed ^^).
