Thanks a lot for all the suggestions, but after I tried every possible combination of ram it didn't work any better...
I even reinstalled ePSXe, to no avail.
Now I think it may be a windows problem because I remember that just after having made a clean install (Windows + Audio/Video drivers + DirectX 8.0a) I tried ePSXe and it worked perfectly smoothly.
But then I continued to install programs (Office 2k, Easy CD 5, forceAspi 1.7, Etc...) and tried it back and it was doing the roller coaster effect...
Has anyone ever experienced this or something similar?
Could ONE application influence so much ePSXe's performance?
Help would be appreciated!
(for my specs, see the first post of the thread)