What exactly does it mean that the new Ivy Bridge CPUs have PCI Express 3.0 support? You can already connect a PCIe 3.0 card (7970 is the only one, right?) to existing Sandy Bridge processors provided you have a compatible motherboard. So what would the Ivy Bridge processors offer over Sandy Bridge in terms of PCIe 3.0?
I'm planning to build a gaming PC around 7970. Just wondering if I should wait for the Ivy Bridge..
you could run a 7970 on a pci-e 1.0 x16 which is equivalent to 2.0 x8 or 3.0 x4, without performance loss, there is just too much bandwidth provided by pci express, ivy will be the first pu with native 3.0 support, this will not translate into improved gaming performance, however, massively parallel raid and storage solutions once fast enough will show substantial benefits
I would say that a PCI-e 1.x slot would bottleneck a HD 7970. However, there should not be any issues with bottlenecking if you stick the HD 7970 in a PCI-e 2.0 slot.; there is enough bandwidth for it.
Overall, the increase in processing power from Sandy Bridge to Ivy Bridge will probably be around 6% in my opinion; some people estimate as high as 10%. Most of Intel's efforts went to the Intel HD 4000 graphics core which is estimated to be about 60% better than the Intel HD 3000; at least's that's Anandtech's opinion.
The smaller die size could be mean that IB CPUs may be clocked slightly more than SB CPUs. Perhaps there may be better overclocks as well, but that is pure speculation at this point in time.
If you can wait for IB, then wait. You'll get a little better processing performance. Otherwise, just build your PC around SB. The next big step up in CPU performance will not happen until Intel releases Haswell (mid 2013).
Okay. That helps a lot. So the boost in processor performance itself will be marginal. Another dilemma is whether to wait for Nvidia 600 series. But that's for a different topic.
Does this mean that if I plug in the 7970 into a system with a Sandy Bridge CPU and a PCIe 3.0 ready motherboard, I'll still be using PCIe 2.0? I understand that it won't matter for performance, just making sure I know what I'm doing.