I can open the internet,check my e-mail but suddenly,my monitor
freezed.I don't know where's the problem,is it my modem?or the o.s.,or my hardisk? :(

It could be any of the above , but more likeley a system freeze , Try the CTRL_alt_del combo , if you get no response to this then perhaps it is hardware , I sometimes get a simmilar situation where the only life I get out of my system is mouse movement. If all else fails try a clean install , or if you have a spare try a new install on another drive.

yep, try what raid said, if it still does it after a clean install of the OS, it's most likely hardware related

Thanks,I did that already,and nothing happen.Good for
you can still move your mouse.Anyway I will try the clean install,then I'll give you the feedback.

Yo,
Clean Install is done,but still the same.Maybe I have
to change my hardware.But you know what, It says
on the modem it's xp supported.Shi.. to this hardware
anyway,thanks for your response.

You know it could also be your Video card! I had a system freeze up. But it was just image on the screen that was freezeing, not the PC. Also check your Fans and make sure they are running.
And while you have the case open, it's a good time to clean it out.
(use canned air to blow it out)
(some of your cards will also have fans on them)

I had a bizarre crash, HD #2 was intermittantly bad. It crashed my system. I put it in an external usb 2.0 adaptor and when it decided to crash it froze the system. Damdest thing. Gonna buy a new #hd tomorrow. These computers are like....hestitate to say, cuz it's politically incorrect and there are some of those wonderful ladies present. :)

I did the clean install but this time Im using the xp.
but still the same.So I decided to check the modem,
and transfer to another slot,then...now its working.
Now I can open my homepage everytime I went
home:http//www.b1forums.cjb.net/ :D

You are on dial up. You had an irq conflict between your mouse and your modem.
A classic problem seen more often on windows 95/98!

Com 1 cascades to 3, and 2 to 4. So if your mouse was on 3 and your modem on 1, your computer will freeze.

By moving the modem to a different slot, your irq changed for the modem.

And unfortunatly, windows xp likes to put all devices in what order it wants and leaves little room for playing. If I remember correctly, by manually setting an irq in xp, the os will say "FINE" and offer no more solutions to you - in other words you must configure everything yourself.

So you did the right thing - move to an empty slot and continue to allow xp to assign your device an address. ;)

Glad you fixed it. Now slightly offtopic, but dont use:
http://www.b1forums.cjb.net/ - use www.betaone.net

the CJB address was a temporary redirect we set up. It will load slightly slower, and has popup adverts.