Just a heads up to people who haven't been following the GPU news, but nVidia and ATI are due to release new video card lineups within the next 6 mo. nVidia will be GTX 6xx series and will be moving to a new 28 nm core which is supposed to double the compute power of their current Fermi architecture. ATI is planning to release their 7xxx series lineup of cards as well, which (*I think*) will also be a 28nm processor design as well. This may mean that if you stick it out for now with low/no gpu acceleration for the next few months, you will be able to buy either the current line of GPU's at a better price or the new line of GPU's and get a lot more crunching out of them.
Also, while it may not necessarily be true of Vegas, in programs I've used that are cuda accelerated, there is usually a direct correlation to both the number of cuda cores, the amount of memory, and the memory bandwidth in the card to the performance gains achieved. For example, my 2 GTX 260's with 216 cores each, have a 448bit memory bandwidth and most newer cards have much less bandwidth but more memory, however my 2 cards together, tend to equal the power of a current single 570 in applications that utilize multiple cards due in part to the larger memory I/O even though it has smaller overall memory.
In video applications I think that increased video card memory is often quite beneficial, so it may be that if you're doing high resolution work ( eg HD, 2K, 4K ) or lots of layers of video, you may be able to handle more with a higher memory video card than with a lower memory one, so it may be of interest to you to buy one that has additional memory.
This is just my experience with video cards, and it may or may not be representative of the implementation in Vegas, but these are just general knowledge points that are true of most GPU accelerated applications I work in.
HTH
Dave
Also, while it may not necessarily be true of Vegas, in programs I've used that are cuda accelerated, there is usually a direct correlation to both the number of cuda cores, the amount of memory, and the memory bandwidth in the card to the performance gains achieved. For example, my 2 GTX 260's with 216 cores each, have a 448bit memory bandwidth and most newer cards have much less bandwidth but more memory, however my 2 cards together, tend to equal the power of a current single 570 in applications that utilize multiple cards due in part to the larger memory I/O even though it has smaller overall memory.
In video applications I think that increased video card memory is often quite beneficial, so it may be that if you're doing high resolution work ( eg HD, 2K, 4K ) or lots of layers of video, you may be able to handle more with a higher memory video card than with a lower memory one, so it may be of interest to you to buy one that has additional memory.
This is just my experience with video cards, and it may or may not be representative of the implementation in Vegas, but these are just general knowledge points that are true of most GPU accelerated applications I work in.
HTH
Dave