Yeah that should run just fine with High End textures.
No, nowadays those are concidered relative low resolution, on averidge they are 1024 x1024 and the maximum size is 1024 x 2048 for certain walls. The High End packages have as averidge 2048 x 2048 while maximum size is 4096 x 4096. That means on averidge the textures are 4 times bigger.
The sizes on the 2nd CD are pretty much the same specs as for the Low End S3TC packages(which is purely coincidental btw)
Theoretically we could go one step higher and make all textures 4096 x 4096 on averidge

But you would need a monster of a videocard for that lol. And i would need even more bigger hardrives i got now

to be able to store the project.
Effectively there's no game worldwide, and there wont be any game for yeaaaars to come that beats the resolution Unreal and UT have with the current S3TC textures. And that includes brandnew games like UT2004, Crysis, UT3, COD4, comparably those are considered low resolution games.
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