I'm having some issues that I would like to get some advice. We have a laptop computer that we have been using for about a year and usually use Chrome as our browser. All of a sudden Chrome got really slow so I ran Super Anti Spyware and it found some tracking cookies that it deleted. I then went to update Malwarebytes and the update failed. I tried restarting the computer and even doing it in safe mode. So instead of messing with it I reformatted the laptop back to factory defaults on Windows 8. I upgraded to windows 8.1 and applied all of the updates and installed Avast as my AV. I put Chrome back on my computer and it is still running horribly slow. It takes about 15-20 seconds to launch and bring something up on the screen. I installed Firefox and it is much faster, but as I add my add-ons (adblock plus, WOT, trafficlight, and lastpass) it is getting slow too. I installed Malwarebytes again and ran a scan and it found nothing.
Last night we got the email from the credit card company that our credit card got hacked at 2:30 in the morning. I don't think the incidences are connected, but I'm starting to get concerned. Is there anyway to check to make sure the lag I'm seeing in Chrome and Firefox (to a much lesser extent) are not connected? I'm wondering if I need to take all of my computers off of the network and rebuild them, In additon I would resett the network back to its default and setup a new ISID and password, but I don't know if that would help or not.
Any advice would be greatly appreciated.