Mark has an old PC and his sound card broke. He knows it isn't worth fixing, so he's wondering if there is an external sound card option? Leo says yes! USB sound cards are available, and they are even better for the computer because they don't pick up the fan noise of the computer itself. Mark will want a USB DAC. They range in price from affordable to expensive. Check out the Syba USB Stereo Audio Adapter. It costs just $8!
There's also FiiO DACs from $25-75 and up. There's a high end one from Dragonfly, which is about $150.