I've got to ask, is there an option in the GS plugin to disable stretching of the image? Even at 640x480 (standard size) it has some strange artefacts, especially noticeable with 2D stuff like the text in Tekken 4. On the real machine it's clear and rounded instead of doubled at the bottom edge of the letters.
I could be completely wrong, but wouldn't a direct image output to the screen be a lot faster? I have noticed in ePSXe that Dr Hell's "simple" GDI plugin can be faster than Pete's best in some cases (e.g. mirror stage in Tekken 2).
The same problem happens with the N64 emulators (look at Mortal Kombat Trilogy or Mario Kart 64). However MESS doesn't exhibit this, since there is no stretching or resolution changing, apart from the final image which is a basic "stretch to fill screen". Still, I wouldn't want to see MESS emulating a PlayStation 2 until the Core 2 Duo is labelled a 486 in terms of speed (as of 2007).
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You cannot run from your own bunghole.
Specs: Intel Celeron 2.8GHz | Windows XP Pro SP1 | 1GB DDR | ATi Radeon 9550 256MB - yes, this PC gets a nice 53FPS in Tekken 4 in PCSX2 0.9.4. Divided by 100!