Some of my specs are:

Intel 3
512 MB of RAM
498 MHz
Windows XP

How can I customize Nexuiz to make the performance of the game better and faster. The game runs very slow, and it skips frequently as well as the sound? Any suggestions?

r_picmip 60

and maybe using tinynexuiz instead, maybe. to improve the loading times.

What video card is in there? If you've got a ati rage pro then you're SOL.

Do you know where I can find out what GFX card I'm using? I never really checked that stuff before. But I will try that and if it does'nt help then I will edit.

You can look in Window's Device Manager.

As mentioned in the FAQ.html you can open the console with shift-escape and enter:
exec low.cfg
vid_restart
It will not look as nice but should be much faster now as it will disable most (all?) effects..

Ok I found my GFX card and it is a Intel(r) 82810E Graphics Controller. Sounds pretty basic to me.

it is..

very

try executing low.cfg as mentioned, then vid_restart. You wont see much of the pretty stuff, but you will be able to frag

lol, ok I'll do that. I am going to find a better GFX card soon or buy another PC.

In general, on-board GFX cards are not good enough for anything execpt office work So it might be an idea to get a card (mobo) cheaper thatis without onboard GFX, and put some more money into the GFX card. Somewhere on this foruym is a list of recommended video cards.

There recommended video cards list can be found here:
http://www.alientrap.org/forum/viewtopic.php?t=349

Bah, I was able to get onboard gfx card running nex decently (hint:Texture quality needs to be low, and all effects should be off, except maybe for particles). Course, with that processor its kinda iffy.

I should be buying a new one next week. To fix this problem.