TR Forums

So I was snooping around, thinking about what my next upgrade is going to look like when I happened across a link to this;

http://nvidia.custhelp.com/app/answers/ ... EzbE45X2s=

and that led to this;

http://www.geforce.com/hardware/desktop ... ifications

I noted that they were refering to the SNB-E PCI Express 2.0 platform. Notice the PCI Express 2.0. I thought that was strange. Isn't the X79 chipset suppose to support pci-x 3.0? Looking around Intel's website anything I find related to the X79 chipset only mentions pci-x 2.0 or 2.1. Any of the motherboard manufacturers web sites all claim pci-x 3.0 support.

Was I skimming through the few reviews I looked at too quickly? Did I miss another important memo?

h

IIRC, Intel wasn't able to get PCIe 3.0 working/validated in time for the x79/ LGA 2011 launch. The thing that saved them is that SB-E processors have a rediculus amount of PCIe graphics lanes ( 40 ) and even the AMD 7970 Ghz edition can't fully saturate 16 lanes of PCIe 2.0. Having PCIe 3.0 makes a much bigger impact in IVB since they only have 16 lanes of PCIe 3.0 (=32 lanes of PCIe2.0). In summary, I wouldn't worry too much about it at this point.

DPete27 wrote:

IIRC, Intel wasn't able to get PCIe 3.0 working/validated in time for the x79/ LGA 2011 launch. The thing that saved them is that SB-E processors have a rediculus amount of PCIe graphics lanes ( 40 ) and even the AMD 7970 Ghz edition can't fully saturate 16 lanes of PCIe 2.0. Having PCIe 3.0 makes a much bigger impact in IVB since they only have 16 lanes of PCIe 3.0 (=32 lanes of PCIe2.0). In summary, I wouldn't worry too much about it at this point.

The UEFI BIOS on my X79 motherboard allows me to select either PCIe 2.0 or 3.0 for my two main x16 slots. And GPU-Z reports that the HD 7000 card I have is working in PCIe 3.0 mode when I have it enabled in the BIOS. I don't know if that is conclusive evidence or not. What I have noticed is that the motherboard is less stable when overclocking the FSB (BCLK) speed when in PCIe 3.0 mode. Furthermore, I haven't noticed any performance advantages in games/benchmarks when running in PCIe 3.0 over 2.0... So I leave it at PCIe 2.0.