Help with PCIe Lanes 5820k vs 6700k

[razer26]

I'm planing on building a new PC, Initially with one 980ti and a M.2 Nvme SSD. I plan on expanding this build later with an additional GPU for 2-way SLI, and possibly an additional M.2 or PCIe based SSD, something like the Intel 750 series SSDs or using a PCIe to M.2 expansion slot like the ones provided by ASUS for the x99 or z170 delux boards. My gut tells me that I need the 5820k in order to support so many PCIe devices as the GPUs will be in 8x configuration, with the 2 SSDs adding another 8 lanes, for a total of 24 PCIe lanes.What confused me was that, I saw a build guide on PC Partpicker, in which the builder used a 6700k, with 2 980tis in SLI, a M.2 SSD and a sound card, which exceeds the 6700k's max PCIe lanes of 16. Am I right? I should stick with the 5820k right?

 

[Ximerous]

Remember something that runs x16 lanes like a GPU can also drop down to 8/4 just with less bandwidth, for most GPUs x8 is fine. However IF you setup your PC as you specified above, because the 6700k has only 16 lane support and having two GPUs and more, the 5820k would be better. Other wise(on the 6700k) a GPU would be set to x4(sli doesn't support x4) lanes which would bottleneck a 980. If you are only going to have one GPU with the PCIe SSDs or ONLY Two GPUS with NO PCIe SSDS go for the 6700k because its skylake and upgrading to the new stuff such as ddr4 is a good idea if you have the money. You shouldn't see any bottle necking of the 980 on 8 lanes. BUT if you are doing what you said(980Ti SLI + PCIe SSDs), getting a CPU with more lanes is the right choice. Though I recommend the 6700k(more upgrade ability) with SATA based SSDs. Unless you have like 10Gb/s internet and need the read/write speeds. Hope this helps, and please feel free to correct me anyone.

 

[razer26]

Thanks!

Remember something that runs x16 lanes like a GPU can also drop down to 8/4 just with less bandwidth, for most GPUs x8 is fine. However IF you setup your PC as you specified above, because the 6700k has only 16 lane support and having two GPUs and more, the 5820k would be better. Other wise(on the 6700k) a GPU would be set to x4(sli doesn't support x4) lanes which would bottleneck a 980. If you are only going to have one GPU with the PCIe SSDs or ONLY Two GPUS with NO PCIe SSDS go for the 6700k because its skylake and upgrading to the new stuff such as ddr4 is a good idea if you have the money. You shouldn't see any bottle necking of the 980 on 8 lanes. BUT if you are doing what you said(980Ti SLI + PCIe SSDs), getting a CPU with more lanes is the right choice. Though I recommend the 6700k(more upgrade ability) with SATA based SSDs. Unless you have like 10Gb/s internet and need the read/write speeds. Hope this helps, and please feel free to correct me anyone.

 

[Ximerous]

Thanks!

Remember something that runs x16 lanes like a GPU can also drop down to 8/4 just with less bandwidth, for most GPUs x8 is fine. However IF you setup your PC as you specified above, because the 6700k has only 16 lane support and having two GPUs and more, the 5820k would be better. Other wise(on the 6700k) a GPU would be set to x4(sli doesn't support x4) lanes which would bottleneck a 980. If you are only going to have one GPU with the PCIe SSDs or ONLY Two GPUS with NO PCIe SSDS go for the 6700k because its skylake and upgrading to the new stuff such as ddr4 is a good idea if you have the money. You shouldn't see any bottle necking of the 980 on 8 lanes. BUT if you are doing what you said(980Ti SLI + PCIe SSDs), getting a CPU with more lanes is the right choice. Though I recommend the 6700k(more upgrade ability) with SATA based SSDs. Unless you have like 10Gb/s internet and need the read/write speeds. Hope this helps, and please feel free to correct me anyone.

No problem!

 

[narun2001]

Thanks a lot for this question and answer This was exactly what I was looking for and I am now convinced that i7-6700k is what I need along with a Titan X and a PCIe based Intel SSD(4x). However, both the GPU and the SSD put together would need 20 lanes. Does this mean that the GPU will start running at x8 and would there be a drop in performance? And could you please suggest a good motherboard to go with this?

 

[Moshe16]

What about 2 rx 480 which cpu is better and why

 

[uguv]

This is a really old thread and has all kinds of bad information in it. I would start a new thread, but I'm sure either CPU would work fine for crossfire rx 480s.

 

[awhite32]

Okay, no one has addressed this problem accurately, and lots of people probably didn't buy the awesome i7 6700k because of this thread, as I was one. Yes, the CPU has only 16 lanes, and these are meant to be 100% dedicated to the primary video card if one is added. The Z170 chipset this CPU is paired with adds an additional 20 lanes which are used for the other slots and M.2 devices. So, you can absolutely run a video card at x16, as well as several m.2 devices without running out of lanes, as the system gives you 36 total.