As the subject line says: can any motherboards support two dual-slot PCIe graphics cards and three PCI cards at the same time? There are certainly boards with two physical x16 PCIe slots and 3 PCI slots, but it looks as though most, if not all, will lose at least one PCI slot in actual use because the space is blocked by the cooler of a dual-slot video card.
If there are any such boards, are any of them Crossfire (rather than SLI)? And x8/x8 Crossfire rather than x16/x4 or any other combination? (Where are the damn x16/x16 Crossfire boards anyway?! )
If, as I suspect, no such board exists, is there at least a high-end Crossfire board that will allow two PCI cards plus two dual-slot PCIe graphics cards at the same time, and also allow a third PCI card if one of the graphics cards is removed?
What goal are you trying to achieve? Do you already possess the PCI cards you need to insert? If not, you might be able to use PCIeX1 cards for one or two of them instead of PCI cards. I'm not sure why you would even consider using 2 PCI (not PCIeX16) video cards, unless you have a lot of monitors to plug in (was that a typo?). If that is the case, and you don't care about performance, then you can just get single-slot PCI and PCIeX16 video cards and fill the thing up.
I'm not sure why you would even consider using 2 PCI (not PCIeX16) video cards, unless you have a lot of monitors to plug in (was that a typo?).
Yes, it was a typo - I of course meant PCIe, as I had already specified twice farther up the post. Should now be corrected.
If Creative were to launch a PCIe version of X-Fi, that would ease the strain a bit, but until they do I need a PCI slot for that. The second PCI card would be a Sweetspot video capture card. The third is a bit fluid at the moment. One possibility is a hardware MPEG2/MPEG4 decoder with PDI output (e.g. RealMagic XCard). I can probably work around that using a software player, but there are various other things I may need the third slot for - external SDI video capture, for instance (as well as the RGB/component capture supplied by the Sweetspot card, not instead of that).
The closest I know of is DFI's RD600 board for the Core 2 Duo. It's a x8/x8 Crossfire capable board with 3 PCI slots, but one of the PCI slots is blocked by a dual slot cooler on a second card.
I barely know any AM2 boards though because seeing as I go for performance, right now AMD has no place in my heart.
So yeah, the DFI RD600 board (I can't remember its full name, just google DFI RD600) is almost perfect for you. If it's an ATX board you want, I don't see how you could find one with 3 PC and two PCI-e dual slot... there just isn't room. Of course, nothing's impossible I guess.
There's a reason why they have the slot PCI-e and PCI block each other. From my experience the older ones don't cuz of the bandwith of the south bridge will get chocked pretty bad. Some would prevent from booting the pc. But with my new mother board I wasn't able to use the rest of the slots since the graphics card are blocking it. But newer boards like the QuadSLI Gigabyte can support when all slots are use, if it's possible since it has higher bandwith.
I remember my old system, an AGP card, network card, sound card and tuner prevents the system from booting at all. Probably the power is chocked in the first place and I'm sure the board is not able to support running these cards at the same time anyways.