Hmm... My wife has Slackware running on a p3 600mHz with 128mb of ram with xfce and it flies!
Then again, she isn't trying to run Eclipse on it...

more ram

I've had quite a bit of experience on this issue of Windows XP running faster than Linux.

About the middle of last year, I started on a project of converting some 20 boxes from XP to linux. The typical spec was as follows:

- Via samuel 2 processor at 760MHz
- 128MB or 256MB RAM

In terms of speed, I found that Puppy Linux and SliTaz ran quite well indeed, followed by the slackware-based distros Zenwalk, Vector Linux, Wolvix, GoblinX and NimbleX (even KDE ran acceptably on the 128MB machines with these distros).

I couldn't even get PC Linux OS to install, TinyFluxOS did though. Fedora 7 (forget about 8 or 9) ran like molasses, as did Ubuntu (Edgy Eft).

Famelix (based on Debian Lenny) ran slowly, at least it did run. Can't say the same for sidux. Knoppix ran OK.

My conclusion is that, outside micro distros, slackware-based distros are best for low-spec hardware.

Next time you try that out, you could try actual Slackware and actual Debian also. You might be pleasantly surprised.

On most machines I have worked with, I have always felt that RAM is much more important than the Processor. My suggestion to people has always been to stock up to maximum RAM even if it means getting a slightly older (slower) processor.

I actually believe that most machines today are Limited by the amount of RAM they have.

Sometimes XP is faster the first month after installation. After 6 months and a bunch of software installed and uninstalled, they are very similar in performance terms. After a year of intensive work, think about reinstalling XP. Your Linux will probably be running like the first day... if not faster.

Improving performance?. Sure. As said before, install only what you need, for me this is the most difficult part having so many free software packages available... :P

You can play tuning the kernel, recompiling latest with Preemption if it is not (zcat /proc/config.gz |grep CONFIG_PREEMPT) and using the appropiate filesystem. Some are better for large files for example while others are for many small ones. Ensure DMA for disks and all that stuff you can easily find googling a bit.

Forget about Gnome or KDE.

Enjoy!!