I'm using Fedora 13, but both KDE3 and KDE4 are compiled and installed manually.
I hate Fedora's default GCC flags, they are insane.
If you know php just fix pts.
I run KDE4 on my grandparents computer which they use for email internet etc... and KDE4 is definitly less optimal than KDE3
It shouldn't require more than a 2Ghz celeron and 512Mb ram to run the desktop itself snappily (which it doesn't)
I still run KDE3 on my laptop from the kde-sunset overlay on gentoo just because I like it that much more interface wise... some of the utilities are more polished in KDE4 but meh... I dislike the whole UI rendering and caching mentality they are using it makes it feel sluggish IMO compared to KDE3 it could be some other completion that causes it but that is what comes to mind.
If you think KDE4 uses less ram I don't know what you must have been smoking... its bigger and slower. The exception to that might be quad core desktops with Nvidia graphics there I can see how it might be faster.
That's memory usage of kubuntu lucid on old thinkpad T40. One of the biggest memory hog is chromium browser. after closing that:Code:free -m total used free shared buffers cached Mem: 496 484 12 0 12 191 -/+ buffers/cache: 279 217 Swap: 1027 4 1022
So memory usage drops from 279MB to 187MB only closing browser with one tab open.Code:free -m total used free shared buffers cached Mem: 496 372 124 0 10 174 -/+ buffers/cache: 187 309 Swap: 1027 11 1016