What is the best antivirus that has low CPU usage for my laptop

Download and install the FREE version of Malwarebytes (linked below). Check for and allow it to install an updated definition file. Scan the PC and delete / quarantine any adware / malware / etc. found. Reboot and repeat. Make sure you have an antivirus running too - Security Essentials from Microsoft is also linked below.

Malwarebytes Software

Microsoft Security Essentials

It might have 3 reason:
1- low hardware ability which needs to be upgraded
2- your system have virus that uses hardwares and doesn't let other applications work easily and you need to clear them by antivirus
3- you have many background apps that takes big part of RAM and CPU usage which you have to close them through process tab in windows task manager and remove them from start up list through start up tab in msconfig
run>msconfig>

You have too many programs running in the background, or if you have Norton antivirus it will do that sometimes, or you have a virus I use windows security its free!

Avast is definitely the best free software out there. It's reliable and you can tone down it's memory usage depending on what you want.

Hi:
Most likely your laptop has too many things running, and other issues.

If you can, the best bet is to save all your important files and pictures, and do a system restore to factory specs.

If you can't do that, try some other things first:

Make sure you have a good antivirus program running on this laptop, and scan the entire hard drive. If you don't have a Antivirus program,
You can download a free one , that works well, at :
www.free.avg.com

Next, go to control panel, ad and remove programs:
work your way down the installed program list, and uninstall anything that is a trial program, any toolbars that you might have installed, or any programs that you don't want or need.

Next, run disk clean up , then disk degragmenter, and hopefully ;you gain back a little speed!

could point to both hardware and software issues..
but first check software issues. can be due to virus/spyware running.. check taskmanger and lists the processes by cpu % ... this will give you the process which is gobbling up the cpu cycles. make note of the file and track it down in hard disk. you will then have to research what it is for.

if you have a antivirus installled it may be possible that it is virus scanning the disc.

hope this helps

I guess it could be a virus, avast is not the best antivirus in my opinion, try to get a norton antivirus or NOD32 update it and run the scan, it ocuurs when a replicating virus copies files to all your HDD and is always busy...making system busy...and one more thing there could easily be a copy of the virus in your pen drive as well...

Sometimes the best solution is to save to disk the important things and just reinstall everything. 

You'll need to look at the Processes panel in the Task Manager to see which processes are consuming your CPU cycles. If you click on the CPU column heading, the process list will re-sort based on CPU usage. If the list appears to be arranged low-to-high ('00' at the top), click on the heading again and the list will reverse so that it appears high-to-low ('00' at the bottom). Once you identify the contributing processes, you can troubleshoot them one-at-a-time.

are u using amd turion ... in the case of laptops the temeprature of near 65 can be said as normal antivirus and hidden virus activities can also increse cpu usage and cause over heating . i am using amd turion i usally get temperture upto 65 dg . note at which processes the cpu temperture increases