Author Topic: Running PCIe x16 on a x4 port? (Read 200 times)

Krusty · « **on:** September 26, 2006, 12:45:55 PM »

A couple of motherboards with dual AGP/PCIe say they have the PCIe port really rated at 4x. If you stick a GeForce 7000 series in there is it going to severely down-rate the card? How much of the "x16" is truly used? I know the upper limits are nowhere near being reached yet. Heck even AGP hasn't maxed out yet. However, before I go that way I want to be sure it'll be a good move, and not one that will lead to crippling fps and the like because the port is sub-par.

Krusty · « **Reply #1 on:** September 26, 2006, 01:29:13 PM »

Heh, answered my own question:

anandtech forums were talking about this, and in relation to the mobo I was thinking of, the fps hit when running a PCIE GeForce 7900 is only about 11% (and that's one of the TOP end cards) as compared to a full x16 PCIe slot.

Sancho · « **Reply #2 on:** September 26, 2006, 02:59:39 PM »

you saw this, right? basically, identical video chipsets will be slightly slower on PCI-E 4x ports than AGP 8x ports. But not massively slower.

Krusty · « **Reply #3 on:** September 26, 2006, 04:58:27 PM »

Ah, no I hadn't. I did a google search and found a thread in the forums with about 8 pages on this mobo. One had a link to one article somewhere on anandtech and said about 11% but, reading the AGP/PCIe comparison I don't know really.