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gamer4eva
05-02-2006, 10:03 PM
my motherboard asus p5vd1-x has both agp and pci-express combo graphix but for pci-express it says 16x slot but only 4x max mode what does this mean:stars:

Seedler
05-03-2006, 01:22 AM
maybe 4x times 4 =pci 16?:wacko:

lynx
05-03-2006, 09:10 AM
Pci express slots have a number of "lanes", potentially up to 32 though I don't think anyone has gone beyond 16. Each lane operates at the same speed, so the more lanes the faster. Obviously the more lanes you can accomodate the wider the physical slot needs to be.

There are two definitions for a pci express slot - the number of lanes and the physical size of the slot. The number of lanes can never be more than the physical size, but it can be less. The same is true of cards designed to fit these slots. The physical size of the card and the slot have to match.

This mobo has an x16 sized slot so that it can take standard graphics cards, but only 4 of the lanes are wired up, so it is actually only an x4 slot and consequently runs slower. Whether you would actually notice the difference depends on the graphics card and the sort of applications you run.

It would have been much more sensible if they had specified different terms for the slot size and the number of lanes, but the "experts" didn't think of that so we are left to sort out the confusion.

clocker
05-03-2006, 10:56 AM
This mobo has an x16 sized slot so that it can take standard graphics cards, but only 4 of the lanes are wired up, so it is actually only an x4 slot and consequently runs slower.
So basically you got screwed.
An AGP slot (dying technology) and a semi-functional PCIe slot (only capable of supporting 1/4 the performance of a full PCIe card).

Hope they bought you breakfast.

gamer4eva
05-05-2006, 04:26 PM
ahhh your right man doesn't matter im not really all that fussed. well to be honest i got no choice