How many PCI slots can I have is one of my major concerns when I come to buy a motherboard. It is true that not many people need more than 5, especially those aim to buy "All-in-one" platforms. Technically speaking, all-in-one board's internal data transfer rate should be somewhat faster than those need external cards. It is because "communication process" is skipped. However, if one of the embedded function such as built-in display or audio function has been malfunctioned, buying a new board or returning to dealer is the only way out. In the past, most motherboards were not as user-friendly as their modern fellows. Hardware conflict due to scrambling for available IRQ resources is common. A classic example is most legacy ISA modem cards can never "get along" with the other ISA sound cards. I still remember I bought a very expensive Gravis Ultrasound sound card (ISA interface) some years ago, I could never install it successfully after trying whatever I could.

For those modern motherboards, such conflict becomes rare because of the genius elaborate design on data bus architechture and something called "IRQ routing" that allows IRQ sharing between various add-on cards requesting the same IRQ. However, I do notice conflict still happens if you plug in a PCI card in the closest PCI slot next to the AGP slot in some boards. Some thoughts can be shared here for freeing IRQ and hardware troubleshooting:

1. Disable all COM ports in Bios menu if you do not need them. I bet very few people still connect their "external modems" to the COM1 or COM2 ports.

2. Disable all onboard audio or display or modem if you plan to use the add-on ones.

3. If IRQ conflict still persists, rearrange the PCI cards to different PCI slots.