In a message dated 5/2/2005 3:17:21 PM Central Daylight Time, [log in to unmask] writes: Greetings, Listers!! I have a 1.8 gb model 5430US Compaq, couple years old that came with USB 1 only. I am considering the purchase of the Belkin USB 2.0 5 port PCI card as an "addon" to obtain high speed USB. The card information specifies use in a PCI 2.1 slot. What differentiates the PCI 2.1 slot from the standard PCI slot? And, for those in the know, should this card work for me? TIA, Vern. Hi Vern, For what it's worth, I just installed a Belkin USB 2.0 4-port PCI card to my 3 year old WinXP system, and it was recognized right away and the ports work fine. All seems to be running perfectly on mine. Donna Parsons PCBUILD's List Owners: Bob Wright<[log in to unmask]> Drew Dunn<[log in to unmask]>