Audio Interfaces native ASIO drivers or Asio4All
Getting guitar software - like Guitar Rig, Amplitube, ReValver Mk II, or GuitarFX 3 - to work on your machine, you may need a new soundcard with ASIO support (i.e. low latency) with native ASIO drivers.

If this doesn't work, you need a new audio interface.
PCI/PCIe
External audio interfaces
USB, FireWire or PCMCIA card/PC CardBus (for laptops).
CD Players
- Tascam CD-GT1mkII Portable Guitar Trainer - the ultimate training and jamming tool for guitarists, vocalists and other musicians. CD-GT1 is a handy little practicing tool to slow down tempo without changing keys, or change keys without changing tempos, and to loop segments you want to learn. You can plug your guitar directly into the CD-GT1mkII's 1/4“ input. It alsp supports a footswitch input for flash start or effects switching. It has 57 Built-in customizable modeling effects (distortions, clean tones, and vocals). Also included is a chromatic tuner.