PCIe Lanes - PCIe 8x vs 16x in SLI

[TheProfosist]

So is 3 way sli possible with a socket 1150 mobo yes or no? Taking into account that some socket 1150 mobo's claim to be able to do 4 way sli?

Possible to do with a plan chip, yes. Natively, no.

[TheProfosist]

Why does 5820k two-way run at 8/8 rather than 16/8?

Probably auto splits the lanes 8, 8, 8, 4. Plus it's only as fast as the slowest card, so you gain nothing by running the first at x16. Also this leaves more lanes open for other stuff.

[Faa]

Why does 5820k two-way run at 8/8 rather than 16/8?

It does 16/8. Think linus just wanted to benchmark the difference between 8x/8x vs 16x/16x, but at 4:58 he says a 5820K is only capable of 8x/8x with 2 cards, so it's far from clear at what he was aiming at.

[Raphael_123]

I learned something new !  

[Leonard]

I learn something new !  

Learnt/learned...you learnt/learned something new!

[Raphael_123]

Learnt/learned...you learnt/learned something new!

you right, I edited it. thanks 

[kaneandtaker]

Please do AMD cards at 16x/4x

[Speedbird]

so what do I want for dual SLI? 

 

I'm at a 3770k ( 4.7 ghz ) now and am looking for a significant upgrade in terms of gaming performance...

4690K.

[trueBearsFan]

So how come watch dogs lost frames from 2-way to 3-way and then again going from 3-way to 4-way. Also he said that he recommends 3-way because the fourth card does not improve performance that much. However, both Far Cry 3 and Tomb Raider gained more fps from adding a fourth card than adding the third card.

[deadbc77]

Awesome Video good info Linus. Here is my Fire Strike Extreme result for 4790K@4.8ghz vs 5960X@stock with R9 295X2/R9 290X for a  Tri-Fire config.Wanted to see if the 40 lanes of Pci-e made a difference.Cards were run @stock.

 

http://www.3dmark.com/compare/fs/2844262/fs/2754975

[NumLock21]

So is 3 way sli possible with a socket 1150 mobo yes or no? Taking into account that some socket 1150 mobo's claim to be able to do 4 way sli?

Socket 1150 board that claim 4-way SLI has a PLX chip that provides additional PCIe lanes to the PCIe slots.

All socket 1150 has 16PCIe lanes, the PLX adds a additional 16PCIe lanes, so in dual it's x16/x16 and 4-way at x8/x8/x8/x8

 

Core i7 5820K only has 28 PCIe lanes compare to all other CPUs which has 40. Some can either spend a extra $200 to get a 40 lane CPU or if your already getting a expensive board like the Asus X99 Deluxe, spend around $100ish more and get a Asus X99-E WS which also has a PLX chip that provides a additional 48PCIe lanes. All socket 2011-3 Xeon CPUs E5 xxxx v3 have 40PCIe lanes

[spacealiens]

Just wondering.  In the 2-way SLI graph in today's video, you have the graph showing 5820k at 8x/8x for 16 pcie lanes.  Is there a way to manually set it to this?  I was under the impression that it would run 16x/8x for a total of 24 lanes, which would also explain why it was also very close.

[Exotath]

This was great I wish there were more videos of similar testings. I had actually just messaged Luke requesting such a vid because I was interested in the 5820K...which I've already purchased.

 

Thanks for listening to your viewers requests!

[Revinval]

As it has been said I would have loved to see AMD cards tested so we could see what 4x does to a card. 

[TheProfosist]

Please do AMD cards at 16x/4x

If it is what I think that 4x will be running off the chipset. I can only imagine how horrible that would be in a number of ways.

So how come watch dogs lost frames from 2-way to 3-way and then again going from 3-way to 4-way. Also he said that he recommends 3-way because the fourth card does not improve performance that much. However, both Far Cry 3 and Tomb Raider gained more fps from adding a fourth card than adding the third card.

Well 2 frames is kinda negligible. Also how much did 3 and 4 way gain compared to 2 way. I find the main issue more than anything now is not SLI scaling well its whether or no the game supports it. Support of 2 way is is common but even 3 regularly has issues.

[LOST TALE]

I learned of that SLI limitation.

and confirmed no perf loss at 8x.

[The Gaige]

So what I got is 2 to 3 cards in SLI with the 5820K would be good for gaming!

 

But, I got a ? what if you use the M.2 port would you not want the 5830K with the 40 lanes, just want to know cause I'm getting a X99 set up in the spring?

[TheProfosist]

So what I got is 2 to 3 cards in SLI with the 5820K would be good for gaming!

 

But, I got a ? what if you use the M.2 port would you not want the 5830K with the 40 lanes, just want to know cause I'm getting a X99 set up in the spring?

yes very much so.

You have to consult the specific manual of the motherboard your looking at.

[Solkia]

I'm glad the difference is negligible in 2-Way SLI. I don't really see myself ever needing more than 2 GPUs.

[RoboRaccoon]

Hmm so here I am thinking of my next build being 2-way SLI + PCIe SSD. So I can do 8x 8x and still have 12 lanes for whatever else I decide to run. I know PCIe SSD's aren't really a thing yet, but hopefully something exciting will happen in SSD land by the time I get frustrated with my current Sandy Bridge build and go for a refresh 

[NumLock21]

Hmm so here I am thinking of my next build being 2-way SLI + PCIe SSD. So I can do 8x 8x and still have 12 lanes for whatever else I decide to run. I know PCIe SSD's aren't really a thing yet, but hopefully something exciting will happen in SSD land by the time I get frustrated with my current Sandy Bridge build and go for a refresh 

M.2 SSD are mostly PCIe SSD based. Most Z97 and X99 boards support them.

[TheProfosist]

M.2 SSD are mostly PCIe SSD based. Most Z97 and X99 boards support them.

Actually most are SATA based there is one PCI-E M.2 SSD at retail right now and it's from plextor.

[7850OC]

i use my card PCIe x16 3.0 on my PCIe x16 1.0  :rolleyes:

 

so... is like use my 7850 in a PCIe x1 3.0 

 

 

(and still rocks)  B)

[apav]

This video brings up an important question for me. I'm using an i5 2500k (PCI-E 2.0, max 16 lanes), a motherboard that has 3 PCI-E x16 lanes (2 of which can run single at x16 or dual at x8/x8, and a third that runs max at x4 and is compatible with x1 and x4 devices), a GTX 780, and a Sound Blaster ZXR sound card (I'm not using the daughterboard). If I understand what I just watched correctly, that would mean my video card is running at x8 and my sound card is running at x1 (since it can't run my GPU at x16 since then I would be using 17 lanes which is 1 over what my CPU can support). This is when I realized something. I plan to get a second 780 in the future, so would I need something better than an i5/i7 to run 2 780's and my sound card? Since I wouldn't be able to run my GPU's at x8/x8+x1 from my sound card (again, over the 16 lane limit), and I can't run a GPU at x4 for SLI, so that means SLI wouldn't work? So my only option would be a CPU that has more than 16 lanes, which, from Intel, are only the Intel Extreme processors?

 

Also, if I took my sound card out and ran my GPU at x16 I would get about a whopping 1 fps increase in most games? Wow, didn't expect it to be so little. Guess I won't be needing an expensive Extreme processor for x16/x16.

[Glenwing]

This video brings up an important question for me. I'm using an i5 2500k (PCI-E 2.0, max 16 lanes), a motherboard that has 3 PCI-E x16 lanes (2 of which can run single at x16 or dual at x8/x8, and a third that runs max at x4 and is compatible with x1 and x4 devices), a GTX 780, and a Sound Blaster ZXR sound card (I'm not using the daughterboard). If I understand what I just watched correctly, that would mean my video card is running at x8 and my sound card is running at x1 (since it can't run my GPU at x16 since then I would be using 17 lanes which is 1 over what my CPU can support). This is when I realized something. I plan to get a second 780 in the future, so would I need something better than an i5/i7 to run 2 780's and my sound card? Since I wouldn't be able to run my GPU's at x8/x8+x1 from my sound card (again, over the 16 lane limit), and I can't run a GPU at x4 for SLI, so that means SLI wouldn't work? So my only option would be a CPU that has more than 16 lanes, which, from Intel, are only the Intel Extreme processors?

 

Also, if I took my sound card out and ran my GPU at x16 I would get about a whopping 1 fps increase in most games? Wow, didn't expect it to be so little. Guess I won't be needing an expensive Extreme processor for x16/x16.

 

Usually the 16 lanes from the CPU are reserved for the full-length slots.  The Intel chipsets have their own secondary PCIe 2.0 lanes that are used for the x1 slots and various I/O controllers like 3rd party SATA or USB 3.0 controllers.  This way, using an x1 slot will not cut your main slot from x16 down to x8.