Installation on Athlon 2600 and XP SP2. Essential to first disable any motherboard audio, and any remnants of other sound card drivers. Initial sustained high CPU activity, preventing good operation, is caused by IRQ sharing and needs attention. Note device will say "no conflicts" but sharing is not a conflict according to XP! Run "msinfo32" to see what is shared. IRQ cannot be set manually, so solution is to move PCI card to slot 2 or 3 (slot 1 being the VGA slot) rather than a high-numbered slot. Also optical in is set by default to the wrong connector and can cause an audio recorder to hang, but this is easily corrected using the excellent intuitive mixer included. Documentation about these quite likely problems really should be included, but at the price I paid I'm not quibbling and am simply astounded at the value for money. Perfect normal soundcard behaviour which is basically to not miss a beat under full audio load either in or out. Perfect recording of 100% modulated optical in, which is the reason I bought this card to replace my venerable Extigy with its constrained USB 1.1 bandwidth. Loads of connectors, good quality components, recommended provided you can find your way around the BIOS and know what an IRQ is.