first of all, i don't know much about computer, so not sure my problem is really a problem or not...

i have a Pentium D , 2.8GHZ duo core with 1G of Ram. don't know why, sometimes when i first turn on the computer, it will "sound" like it's busy for thenext few hours even it's just idling, even i'm not doing anything with it. i hit control+Alt+ Delete, and it shows CPU usage is only 1 to 2 %.
and when this problem occures, it's pretty obvious that the computer is slower than b4 on handling tasks.

so can anyone tell me, what will cause an idling computer to keep doing something by itself??
it's pretty annoying that it makes that "kit kit kit" sound inside for hours even i'm not doing anything with it.

1st, you can check you PC with spyware program
2nd, please check your harddrive with some disk scanning program, sound like you need to replace a new one if you heart "kit Kit Kit" sound.

spyware - http://www.lavasoftusa.com/software/adaware/
HDD Sacn and Repair Program - http://www.freedownloadscenter.c ... ogram_Download.html

thanx for replying.
I only got this computer not that long ago, and my firewall is always on, plus i have windows defender and Mcafee full version on all the time, is it still possible that i catched a spyware or worm?  
and what is the disk scanning program do? just checking if there's any damage to the hard drive?
the 'kit kit kit' sound is the sound of when the  computer's running busy, or when downloading something and the sound of the hard drive. i just thought that, if the computer is at idle, it shouldn't be so busy doing something by itself.

this problem doesn't happen like everyday, only sometimes for afew hours, then will stop.

well... windows defender ...... suggest you logon as safe mode and run couple hours, see it running normal or not. To be honest, I have the same issue after install windows defender. I just uninstall it and every thing back to normal.

Yes, disk scanning program is checking any damage to the hard drive (like bad sector)

may be not enough memory? and the computer is access its virtual memory on hdd? but you have 1G , so it shouldnt be that

It's normal when the system is idle, the CPU usage will still be around 1 or 2 %, because Windows keeps working even you are not doing anything like moving stuff from the memory to the virtual/temp. memory space on harddrive ...
About the click-click noise, I will be more concern on it.  You have to find out where you hear the noise, if it's from the harddrive then you have to notice whether this situation happens always and the system takes long long time to boot up; if that is true, your harddrive may have problem that has to be replaced.

what do you mean your computer is very busy? the hard drive light on all the time? is that kind of busy make your system slow, cannot do anything?  Sometime, may be your anti-virus is doing some background scan.  You didn't mention how big is your hard drive.  About your hard drive noise. some drive are very noise when it read and write data.  Before I had a hard drive are very noisy, I can hear what I drive is bus yor not, I don't need to see it.  If you still scare the hard drive have problem, you can bring it to any computer store to ask them. I don't think they will charge you anything for only listen the noise.

I think you computer is just fine.  The sound you heard is likely related to the indexing service being kick on... the process might take some time depends on how much stuff you have and how large is your hard drive.  As long as you don't hear a loud 'grinding' sound when you access data from the hard drive, your hard drive is probably ok.

That could be the automatic updates of Windows and some of your applications are working behind every times you turn on the system. When all those programs updating are working, they don't need much sources from your CPU, but will use up your memory to cause your system lagging especially if your internet connection speed is slow. Many programs are putting on their "automatic update" or "checking a newer version" by default through your internet, if it is the case, disconnect your internet before you turn on the computer, problem should be gone. Then use an utilities application or Spy Sweeper to edit your startup programs to turn off all those updates and you do it manually when you need it.

thanx alot guys.. cause this problem only happens when i first turn on the computer, and usually will last for afew hours. so i assume it's the automatic update that's slowing me down..but when this happens.. it will really slow down my computer by alot.. for example.. if i wanna transfer a file (around 500MB) from my computer hard drive to my portable hard drive. normally, will take less than 1 min from cut and paste.. but one time, when the computer 'sound busy'... it took almost like 10 mins for the transfering.... i don't know much about computer, and i just thought that i got a duo core CPU,,so it shouldn't be like that lah... maybe P D isn't that mighty after all.. hehe...