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**pSXAuthor** · April 19th, 2007

There seems to be some confusion.. to clarify:

pSX uses SSE (1 and 2) in its PS2 emulation code. But this is not necessary for the PS1 emulation which uses only MMX.

GCC is a bit lame when it comes to controllng SSE support... it is all or nothing. So... the original Linux WIP builds were compiled with SSE support enabled. However... this causes GCC to use some SSE instructions in parts of the PS1 code which means it won't work on Athlons.

To fix this I rewrote/rearranged some code so that SSE is only enabled for the PS2 parts (this was not possible before because of some stuff in header files).

So... the release version (v1.11) should only require MMX unless you enable PS2 emulation in which case it requires SSE 1 and 2.

I am not sure why some people are having problems with v1.11 on Athlons... it definately works for some people I know with Athlons, so I don't think it is the same problem as the one detailed above.

April 19th, 2007	#7 (permalink)
pSXAuthor Emu author Join Date: Jan 2006 Location: In my house Posts: 48	There seems to be some confusion.. to clarify: pSX uses SSE (1 and 2) in its PS2 emulation code. But this is not necessary for the PS1 emulation which uses only MMX. GCC is a bit lame when it comes to controllng SSE support... it is all or nothing. So... the original Linux WIP builds were compiled with SSE support enabled. However... this causes GCC to use some SSE instructions in parts of the PS1 code which means it won't work on Athlons. To fix this I rewrote/rearranged some code so that SSE is only enabled for the PS2 parts (this was not possible before because of some stuff in header files). So... the release version (v1.11) should only require MMX unless you enable PS2 emulation in which case it requires SSE 1 and 2. I am not sure why some people are having problems with v1.11 on Athlons... it definately works for some people I know with Athlons, so I don't think it is the same problem as the one detailed above.