Quote:
Originally Posted by Pyramid_Head
PCI E and PCI are not the same thing, PCI E is much much better/faster than AGP  |
Depends on which size pci-e socket
This is a list of all the expansion sockets based on PCI, AGP and PCI-e:
33MHz/32bit pci socket:
Very difficult to find a motherboard without at least one of these.
66MHz/32bit pci socket:
The socket is reversed compared to 33MHz pci, pci cards with two notches in are compatible with both 33MHz and 66MHz sockets. Very rare.
33MHz/64bit pci-x socket:
Extended version of 33MHz/32bit pci normally found on server motherboards, cards that work in a 33MHz/32bit pci socket will also work in it. Some cards for this socket will work in a standard pci 32-bit socket, as long as the connector doesn't interfere with anything on the motherboard. Quite rare.
66MHz(+)/64bit pci-x socket:
Extended version of the 66MHz/32-bit pci socket, normally found on server motherboards. Cards that work in a 66MHz/32-bit pci socket also work in this socket. As with 32bit pci, cards exist that are notched to fit in both 33MHz and 66MHz(+) 64-bit sockets.
AGP 1x, AGP pro, AGP 2x, AGP 4x:
Old versions of AGP, not compatible with modern AGP cards because of a difference in voltage (3.3V instead of 1.5V).
AGP 1x is the same speed as 66MHz/32-bit pci, or double the speed of "standard" 33MHz/32-bit pci, but with special graphics-specific extensions. AGP 2x and 4x are 4x and 8x the speed of pci, respectively. AGP pro is a longer AGP socket with more power lines.
AGP 8x:
16x times the bandwidth of standard pci, dedicated for graphics card use. Most motherboards with an AGP socket have an AGP 8x socket.
PCI-e x1:
The smallest pci-e socket, roughly the same speed as AGP 1x, twice the speed of standard pci. It is also full duplex (simultaneous send/receive). Standard pci and pci-e are NOT compatible, despite the similar names. pci-e motherboards normally have at least one of these.
PCI-e x2, x4, x8:
Longer pci-e sockets, quite rare. Any pci-e card will work in a larger pci-e socket. x4 are the most common of these, I haven't seen x2 or x8.
PCI-e x16:
Modern graphics card socket, twice the speed of AGP 8x. Modern pci-e motherboards typically have one or two of these. Two can be used to have two graphics cards in a pc linked together for SLI/crossfire.
PCI-e x32:
Part of the standard, but would be huge. I've never seen one.
PCI-e x16 (x1,x4,x8):
A lot of older "SLI" motherboards only had x1, x4 or x8 worth of pins connected in a x16 socket, instead of the full x16. While this is valid under the pci-e spec, it means that the card will operate at reduced performance. Some recent pci-e graphics cards won't work in one of these sockets, mostly "two in one" cards with 2 gpus on one card. Some "SLI" motherboards have a switch to change between having one full pci-e x16 socket and one unconnected (or x1 connected socket) and having two x16 (x8 connected) sockets.
In a nutshell an AGP motherboard will likely have 1 AGP 8x socket and 2-5 PCI sockets, and a pci-e motherboard will likely have 1-2 pci-e x16 sockets, 1-2 pci-e x1 sockets, possibly 1 pci-e x4 socket and 1-2 PCI sockets.
To be honest, if you've got an AGP 8x motherboard it's only a problem if you want to use a really recent card that is pci-e only, but if you're building a pc get a pci-e board, as value pci-e graphics cards do exist and it's more future-proof.
DON'T get a combo AGP/pci-e board, as the AGP socket is likely to be emulated on a pci or pci-e bus (reduced speed and/or compatibility) and the pci-e socket is likely to be only x8 connected (also reduced speed and/or compatibility), not to mention that these combo boards are hideously expensive. They're not worth it!
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