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joedemagio
11-20-2004, 12:02 PM
I have a server style motherboard so it has many slots on it, 8 in total. 1 AGP, 1 PCI-X, 1 EISA, and 5 PCI slots. I have some cards like network cards, maybe a RAID card, and a firewire / usb 2.0 card that would be installed in the PCI slots (PCI-X for the RAID). I thought I heard somewhere that having many PCI slots filled reduced performance, so I am verifying this with you guys. Would having more cards installed reduce system performance?

Amd_Lover2004
11-20-2004, 03:07 PM
Most likley as the PCI slots share the 133MHz or whatever it is the more "stuff" you have on the bus the higher the posability of slowing down your computer. I find it a little less so in server style motherboards but thats just me. Dont know if that applies in all cases or not.

Morgan_Lander
11-24-2004, 08:17 PM
The PCI-X slot should auto-negotiate the bus speed of the PCI-X bus. I don't know if the PCI-X slot is the only link to the PCI-X bus, or if it's got something on-board like a SCSI controller or NIC hooked up to the bus as well.

The PCI bus and the PCI slots themselves won't change speeds as they only run at 33MHz. Same with the AGP.

wayout44
11-24-2004, 09:09 PM
I thought I heard somewhere that having many PCI slots filled reduced performance, so I am verifying this with you guys. Would having more cards installed reduce system performance? In most cases yes you will suffer reduced performance as the PCI bus is restricted to 133MB p/s bandwidth and once you exceed this then the hardware running on it will have to take turns at using the bus and also remember that your IDE and USB controllers are already connected to the PCI bus plus the PCI bus is also used for communication duties between the north and south bridges of your mainboard (also if the PCI-X bus runs off the south bridge then that will also add more to the congestion).