The built-in sound card on most any laptop is weak. They are designed for simple playback, where a 500ms delay is not a problem. Throw in low latency, two way communication(ie;simultaneous record and playback), and they generally fall flat.
An external USB interface will still be almost essential, even if you do upgrade your computer.
With a proper interface, you could probably get a little more mileage out of your Acer.
I'm currently running X3 Studio on a 4 year old Toshiba laptop and the AKAI EIE-Pro USB interface handles the audio duties.
On a side note, this forum is for the now out of production Sonar Home Studio series.
Going forward, you should post your questions in the X Series forum.