TheMiataFanatic

On 9/18/2015 at 4:52 PM, timohour said:

As Tech Inferno Fan noted

EC - mPCIe --> Southbridge Gen2

dGPU-->          Northbridge Gen 3

dGPU on the Gen3 northbridge is wired directly to the CPU as you can see here pg.115.

By the way Gen 3 uses a more efficient 128b/130b encoding resulting in a real bandwith per pair of 984 MB/s out of the 8 GT/s, not 8b/10b. pg.30

On pg.30 you can also see that the configuration with the more Gen3 capable PCIe ports is 1x8 and 2x4, a total of 3 ports. That's what PEG0/1/2 is. In our E6430 it is set as 1x16 and it is dedicated for the dGPU which is the only port you can set to Gen3 speed. (NVS5200M is only Gen2 capable so it is mostly a waste). There are no systems AFAIK that sport an EC or mPCIe port rated Gen3.

EDIT : Just for proof I tried some fiddling with the PEG0 port speed Gen.

Setting variable 0x1f5 to Gen1 will result in the following result

While on default it is set to Gen2 will result to this

Setting this to Gen3 (although it is useless since NVS5200M is just Gen2 capable would have some strange effect on the card clocks. It would clock @ 202MHz and it would have terrible performance... I had to clear CMOS to revert to default clocks and Optimus to work as normal.

Hi! I know this thread is probably dead, but I was interested in connecting my GTX 780 to my E6430 w/NVS 5200m via ExpressCard. What's the highest bandwidth I can do through that and would you recommend that I get an EXP GDC? Thank you.