my laptop becomes slow,cpu usage reaches 100%, even after formatting?

I guess it is because you are having some hardware problems. for temporary solution you can maximize the virtual memory . for that

1. go to my computer -> properties-> advanced-> performance->settings

2. under settings->advanced->virtual memory->change

here you make the number above 2000 which will allow the machine to allocate approx 2gb space for it's swap space. don't worry it won't drain your memory space.

First you need to see if your Laptop is using dedicated Graphics Memory or is it Shared with RAM? If the latter is the case, share a slightly larger portion of RAM for Graphics. CPU getting slow is due to background applications running. Make sure on the right bottom corner there are the bare necessary application icons, rest of them you remove/disable. If the Laptop has been used in dusty conditions, the CPU cooler fan tends to get dirty and spin slower which results in CPU heating up excessively, get it checked from a certified workshop.

Full screen is very processor intensive

You will have to make sure that nothing else is running in XP (not an easy job) to free up as much processor as possible

I often boot slitaz linux or puppy http://puppylinux.org/main/Overview%20and%20Gettin...

from a disc (don't need to install anything) if I am watching a DVD or online movies because the use very little ram and very little processor power

dude i was suffering from the same problem.firstly you should get a cooling pad for your laptop.it may seem surprising to you but its true.the cpu uses 100% of its capacity when cooling needs are not up to the mark.then you should run a spygot scan

Get Rizone Memory Booster ( it works better than others ) and set the boosting period 5 or 10 seconds, plus go to RUN--> msconfig and disable all startup programs. If you want further help, you can at once apply to send me screenshots of your taskmanager program lists or let me tweak your laptop via any remote software. request it anytime by contacting me at lightmaster.in

Well

A good tool I used to clean up and speed up my PC is CCleaner. You can download it for free here http://bitly.com/UrAS6r

It's the best choice.

1GB of RAM is a huge part of your problem. Bump that up to 2 or 3 GB at least. If you have a 64 bit OS installed then take it up to 4GB.

There have to be two issues:

a. Virus Infection (Use Avast free)

b. Corrupt Registry/System errors (Use Reginout )

I am sure it will fix for you.

Add RAM & download Reginout to improve performance of your system.