Stalling effect in Dell notebook with screensaver app

Hi everybody,

I have developed a screensaver based chat application in MFC. The concept is the screensaver keeps running on your computer (images being displayed etc..etc.). A visitor (who's come to call on you and finds you absent from your seat)can press any key on your keyboard to invoke a chatting console. He can type in a message that would be sent as an MMS to your handheld device (mobile). You can reply to that message from your mobile which would again be seen in the chat console.

This works fine and I've tested it on a number of H/W and S/W environments. However, it doesn't deliver the expected performance on the Dell Latitude laptop. I experience a stalling effect (the chat console hangs) say every 10 seconds. This shouldn't be ideally happening since it is a multithreaded app. Time/resource consuming activities like checking for incoming messages run in seperate threads.

I've reached my wits end trying to figure out the reason (let alone the solution). Have any of you experienced a similar problem anytime? Could you help me out??

 

Any stupid processes?(e.g. some versions of Norton Anti-virus)
Any software feeling responsible for your security or entertainment (to show pics or something)
And more importantly there is some software that can be configured to schedule tasks on screen saver (for example BitDefender can scan for viruses while on screen saver) - and what about the indexing service?