PCIe Lanes!

[Cigarjohn]

I need some advice from PC builders. I'm a little confused. Intel's support sucks. What a bunch of idiots, after two support techs and 1.5 hours of wasted time, they seem to not know their butts from a hole in the wall. And it seems no one builds computers that work at Intel. "GO FIGURE"!

Anyway, back to my questions:

I'm looking at building a new system for gaming and light to medium heavy video editing. Now I'll probably use the i7-7700k on the z270 Chipset. Most likely the Asus z270 WS or possibly the Asus X299 APEX or Maximus VI Extreme with the Intel 7800X.

Also will be using one 1080 TI in 1440p with a possible future expansion of SLI in the future but not know.

So getting to my question. The i7-7700k has 16 PCIe lanes and the chipset has 24 PCIe lanes. So does this mean I have a total of 40 PCIe lanes to work with.

I'm asking this question cause I would like to run dual video cards in x16 mode, one M.2 in gen 3x4 in PCIe mode and one x4 sound card. These combined equal 40 PCIe lanes. So my question is if you need more PCIe lanes than the processor can handle, will the chipset kick in with the remainder PCIe lanes needed?

Also, do SSD's and your Optical Drives use PCIe lanes as well? The SSD's are Sata 3 and the Optical is a Sata connector.

Also I noticed the chipset specs state it also uses six Sata 6G ports and fourteen USB ports. Are these an addition to the 24 PCIe lanes?

On RAM, I think I'll be going for 2400mhz at 32 gigabytes.

Thank you in advance.

 

[Korreborg]

As far as i know, its not possible.

You can get 8x 8x for graphics, and the the chipset handles the m.2 and sound card.

But PCIe 3.0 8x is still enough for a GFX.

 

[Cigarjohn]

Ok, thanks for reply. I know that x8 and x16 are very marginal in FPS. Just wanted to know how many PCIe lanes are available to me and if the CPU and Chipset PCIe lanes are combined. I mean, why do motherboard manufactures state that their motherboards can do x16, x16/x16, x16,x16,x8 and x8,x8,x8,x8 modes. I know for video editing x16 will make a big difference. I'm talking about non-gaming video cards.

 

[NeverBackDown]

Ok, thanks for reply. I know that x8 and x16 are very marginal in FPS. Just wanted to know how many PCIe lanes are available to me and if the CPU and Chipset PCIe lanes are combined. I mean, why do motherboard manufactures state that their motherboards can do x16, x16/x16, x16,x16,x8 and x8,x8,x8,x8 modes. I know for video editing x16 will make a big difference. I'm talking about non-gaming video cards.

Boards that do that are generally very expensive and have additional chips onboard That adds more PCIe lanes.

 

[S_I_N]

you'll have 16pci lanes from the cpu for the graphics side of things with normal boards. You'll have 24 lanes from the chipset that are for the various items on the board like sata m.2 and the likes. Remember M.2's are now x4 so if your board has 2 M.2 slots thats 8 of the 24 gone.

Now some higher end board will come with a iirc plex chip (think thats the name or used to be but dont quoate me on it) that will up the pci lane count to add more for the pci lanes over all. I used to run a Z68 board that had 2 x16 lanes cause it had that extra chip.

 

[Cigarjohn]

Ok, thanks for your reply. Yeah, like on the board I was looking at: the Asus z270 WS, the board specs say x16, x16,x16, x16,x16,x8, x8,x8,x8,x8. So I would imagine if you were to run two cards in x16 mode and the cpu only has 16 lanes, I would assume the other 16 lanes would come from the chipset. If not, then why would they mention that the card can do dual x16 slots. Just want to make sure. Also, this board has that additional PLX chip on it for sli, Tri and Quad card setups. But I hope that if I just run one card, the PLX won't degrade my cards performance as it only kicks in if you are using two or more cards. Then again, if I decide I need more PCIe lanes, I can opt for the new x299 motherboard as the 6 core Kaby Lake offers 28 PCIe lanes. But I really don't think I need 6 cores right now for gaming. I don't know of any games that utilize 6 cores. I know there are a few that can use 4 cores.

Your thoughts on this is greatly appreciated.

 

[Cigarjohn]

you'll have 16pci lanes from the cpu for the graphics side of things with normal boards. You'll have 24 lanes from the chipset that are for the various items on the board like sata m.2 and the likes. Remember M.2's are now x4 so if your board has 2 M.2 slots thats 8 of the 24 gone.

Now some higher end board will come with a iirc plex chip (think thats the name or used to be but dont quoate me on it) that will up the pci lane count to add more for the pci lanes over all. I used to run a Z68 board that had 2 x16 lanes cause it had that extra chip.

Funny you should mention your z68 board. I use to run an Asus Maximus IV Extreme z68 with the i7-2600k cpu and the first lane was x16 and in dual card mode, they would be recognized as x8. But I saw a weird hack on Youtube that if you install a x4 card like I used my sound card in the first PCIe x16 slot, slots 2 and 3 would automatically convert to x16 mode. I did it and the bios recognized it as two cards running in x16 SLI. Now I don't know if I was actually getting true x16 SLI out of my cards as dual x16 and dual x8 are pretty much marginal in graphical performance. And not all games scaled in SLI. But the bios did show that slots 2 and 3 were x16 SLI. "Go Figure"!

 

[S_I_N]

Plx chip that's it. My Z68 gigabyte ud7 had that. Gaming wise you'll see no diff from x16/x16 or x8/x8 production wise I don't know. But even with the x299 and 24 lanes you still won't have dual x16 from CPU.

 

[Cigarjohn]

True, unless you get that new x299 10 core or higher processor which comes with 44 PCIe lanes. But I rarely have use for a 6 core cpu let alone a 10 core and I can put that extra $1000.00 to better use than a processor for my uses. But I'm only going to be using a 1080 TI which with work perfectly with the i7-7700k with it's 16 PCIe lane limitations. Unless they start making games that utilize 6 cores, 4 cores is good enough for my needs. I'm just getting tired of building new systems every 3 or 4 years for myself. So I decided to get in the work station realm of boards as they have a longer life spam, better capacitors and they too can be overclocked and can be used for gaming as well. And the expandibility is great on them for future expansions. Hopefully I can get 10 years out of it before considering on building a new system.

On another note, I remember that UD7 z68 board. A nice board I was considering when I chose the Asus board, which I went through 3 identical boards until I got the right one that finally worked. But that's another story. Probably Newegg selling me refurbished boards and not telling me and making me pay full price for them.