Originally Posted by dan330
how big is the file for a 90min movie in MP4??
That depends a lot on the codec (MPEG4 or H264). H264 will be half about the half the size for the same quality as MPEG4, but both will have a MP4 file extension.
It also depends on what resolution and quality you're willing to tolerate. I have found that 640-ish x (whatever) displays nicely on the Evo, and there's really no reason to go up to the full 800 x 484 resolution. If you want higher quality (less motion blur and pixelation), then it would probably be best to encode using H264 to keep the size down.
All that being said, a typical 90-120 minute movie that I've encoded in H264 for my Evo is usually in the 400-500mb range. I'm pretty picky, so at that size the quality is pretty good. The same movie at the same quality in MPEG4 and/or AVI (Xvid, Divx, etc.) would likely be approaching 1 GB. You could maybe get away with backing off some on the quality to get the size down, but if the Evo will play H264 you might as well use that (IMHO).