Geez Baldy....making the insinuation that PCI-Ex16 and PCIE-x16 2.0 are one and the same due to backward compatibility is more ludicrous than stating factually that they are different technologies. Putting a PCI-Ex16 video card in a PCI-Ex16 2.0 slot is not going to make that card work any better...nor will putting a PCI-Ex16 2.0 video card in a PCI-Ex16 slot. They are each specific stages in the PCI Express technology tree, just like every other progression of a technology tree...USB 1.0 and 2.0...IEEE 1394 400/800/S800T...etc...
Stop insinuating that just because it fits that it works the same...because it doesn't.
They actually work exactly the same using the exact same technology with the only difference being in the memory BUS bandwidth, which is twice as much in the 2.0 varieties. When the varieties are mixed, they default to the lower bandwidth.
Lets take some real-world examples:
Person A has a motherboard that supports AGP 2x/4x. This poor soul cannot buy a new video card and has to scrounge up a used one on ebay.
Person B has a motherboard that supports AGP 4x/8x. They can still buy a realtively modern card new, but as soon as they upgrade their motherboard that card will be useless as it won't fit into the current PCIe x16 type slots. They are also locked out of 90% of the available cards on the market based on the numbers of each type available on newegg.
Person C has a motherboard with a PCIe x16 slot. They can choose to buy either a PCIe x16 or PCIe x16 2.0 video card. If they thought they'd upgrade their motherboard at some point they'd probably buy the 2.0 version. Even though they won't get the benefit of the extra memory bandwidth the card will work exactly the same as it's 1.0 counterpart and, when they upgrade their motherboard in the future they will "unlock" the additional performance of the card. This person also has the option of buying a 1.0 version PCIe x16 card and may want to do so based on price considerations. Even though they are buying the older memory interface, when and if they do upgrade to a motherboard that supports 2.0, they can move the card into that motherboard and it will perform exactly as it did in the older 1.0 slotted board.
Person D has a motherboard that supports PCIe x16 2.0. They are most likely to want to purchase a PCIe x16 2.0 video card but, if there's a big enough price differential and they're on a budget, they also have the option of buying a 1.0 version card. Even though it will only use half the abailable memory BUS it will work just the same as it would in a 1.0 slotted motherboard.
