system goes to 100% and stays there and system idol goes to 0 and stays there., and the computer slows down or hangs. only way to fix it is reboot. windows xp

Hi 1red1, High CPU issues can be caused by many factors like:a. Third party security applications like Antivirus, Firewalls, etc. b. Other startup items set to start when you boot your computer.c. Incompatible programs not designed for Windows 7. d. Drivers not compatible with Windows 7.e. Low System requirements (slow processor, little RAM, etc).f. Others.You may use the below methods and check if these help -Method 1: I would suggest you to find out which program is causing the high CPU -a. Right click on your task bar and choose "Start Task Manager" and click the "Processes" tab.b. Click "Show Processes from all users" at the bottom.c. Click the column HEADER named CPU; this will sort the list of programs by the ones that use the MOST CPU at the top.d. Write down which EXE files are always at the top. You may let us know the names of the files causing the issue.Method 2: You can also try a clean boot and check which non-Microsoft service or application is causing the issue. This will also help us identify if any startup program is causing issues.To perform the clean boot follow the step 1 mentioned in the below article and then try checking in this clean boot state -http://support.microsoft.com/kb/310353If the issue gets resolved check which non-Microsoft service is causing the problem; referring to the article and following other steps.After you have finished troubleshooting, follow these steps to reset the computer to start as usual:a Click Start, type msconfig.exe in the Start Search box, and then press ENTER.If you are prompted for an administrator password or for confirmation, type your password, or click Continue.b. On the General tab, click the Normal Startup option, and then click OK.c. When you are prompted to restart the computer, click Restart.Hope this helps.Thanks,Meghmala – Microsoft SupportVisit our Microsoft Answers Feedback Forum and let us know what you think