I'm pondering getting a motherboard that supports VT-d and also the Q6700 and ECC DDR2; the 3210/3200 chipset appears the only option without an upgrade to DDR3.
There are various limitations with the PCI-e cards that may be used on this board and the documentation is confusing. The 3200-3210 chipset memory controller hub datasheet says :
'The 3210 MCH supports either two PCI-E x8 or one PCI-e x16'. This is confusing, as the manual for the 3210SHLC shows it as having a x16 and a x8, but the datasheet shows 2 off x8. I suspect, therefore, it is two x8 slots.
(There is also a x4, but that is off the ICH9R).
It also says 'if a VGA adapter is inserted into this slot (this is referring to the first 'x16' slot) the VGA card will only work at PCI-e x1 speed. This is a chipset limitation'. This sentence does not appear against the other MCH PCI-e slot in the Intel motherboard manual, but does appear in non Intel boards using the 3210 chipset.
The chipset datasheet says 'The 3200/3210 MCH do not support PCI-e graphics. The PCI-e ports are intended for external device attach'.
Can I verify that this is the case and that all MCH slots are incompatible with PCI-e graphics. Is it also possible to understand what the precise limitation is - I presume there is no difference between attempting to run a PCI-e graphics card in an MCH PCI-e slot whilst booting up a normal operating system (i.e. direct hardware I/O), and running the same operating system through VM software (Xen, VMWare etc) accessing the card remapped from a VM box directly to the hardware using VT-d?
I rather suspect my only option here is to go X38/X48/X58 and change the RAM/CPU, or choose one of the Qxx chipsets, if I want to use a PCI-e graphics card at a reasonable speed.
Thanks Edward, I'll probably look at other boards then. The WX58BP would be a possibility with a new CPU/RAM, but the S975XBX2 wouldn't as it doesn't support VT-d (I'm currently using the D975XBX2, which is practically the same).