Hello, I have a old PC on which I've installed Debian.
The specs are:

CPU: Pentium 150 MHz
Ram: 32 mb
Video Card: Voodoo4 4500 (32 mb of ram) (I put that one because the original was a ??? board with 512kb of ram)

Sound Card: SoundBlaster 16 ISA
The Window Manager: IceWM


Is it possible to have Linux Debian and XWindow on such a machine ?
If yes, I want to know because when I start IceWM and that I open xterm (if IceWM don't freeze while booting) and I type "free" in the terminal, it show me that ~750 bytes of ram are not used. Is there a way to have more by closing some utils which i'm not using or by borrowing some ram
to the video card ? Thanks for your answers.

you should be able to. see what services you have running and try stopping them. /etc/rc5.d should be the location of the scripts for services that are running. you probably wanna stop any that your not using. its not an ideal spec pc but you should be able to do it. perhaps try looking for more minmal distributions than debian. als otry using an even more toned down window manager like fluxbox of similar.

Excuse me for such a stupid question, but how I disable services ?

And particularly inetd because I don't need it.

dunno about debian but fedora has a nice thing in kde (k menu -> system settings -> server settings -> services) for setting which services run at startup. i'm a bit of a fedora geek to be honest and i don't have enough time to work behind the scenes as i'd like too unless i actually have too and this isn't somthing i've had to deal with so i can't help much more but maybe try lookinging for more debian specific forums...
sorry for not being much help
pat

Pat, I want to say you that your post would have been useful if the X server was functioning and that KDE would run on a such antiquity but there is ~700 bytes free because the cache eat 18/32 mb of ram
and last i have left linux and installed Windows 98SE on it. At least it runs... but i would prefer linux.

32mb RAM is plenty. A pure command line Slackware install takes 8mb (with a few trimmed services), so you can get in Fluxbox fairly easily. It still won't leave tons and tons for applications (so you will be swapping a lot for heavy RAM applications) but it's definately doable.
And try to get drivers for the voodoo card, that way you will be running using it's hardware instead of the built in software mode, which should makes things at the GUI level faster.
Also, when you type "free", make sure to add the "cached" column to the "free" column to get your total free RAM, since cached RAM is still useable.
I don't know tons about Debian, but I would recommend Vector Linux (it is optimized for older hardware).

Plus... how much memory can that older motherboard support? Buy some. You can order older memory-devices through the Internet. Many computer-stores (other than chains like CompUSA) have a "box of stuff in the back."

While it is a valid academic exercise to run an OS in a memory-constrained system, "chips are cheap." Especially for older systems.

You might also want to try older X versions. Older 3.x versions are much easier on the hardware than newer 4.x thingys.

I used to run Linux with Xfree86 on an 80386DX/33 with only 4MB of RAM and 8MB of swap. It was tight but it ran. By today's standards doing that would be a painful experience.

But to directly answer your question: yes, just download an older Slackware or Redhat distribution, don't even consider running gnome or KDE, and it will run just fine for you.