No SLI Support?

[Omga4000]

Hey everyone,

A bit of an odd question to ask, I actually feel a bit stupid asking it, but I might as well do.

When a motherboard manufacturer does not state that it supports SLI, does it mean that it does not support it natively (i.e without a bridge),
or that it simply CANNOT handle SLI in any way?

If the second is true, then a follow up question:
How come most motherboards do support CrossFire, but not SLI?

Thank you,
Omga4000

 

[junkeymonkey]

amd x-fire only require a slot to be x4 NVidia sli requirement is x8 on the slots that's why even boards that are sli compatible can loose sli capabilities if you add a 3ed card or something that shares the pci-e lanes with the CPU and drops the slots to 8x4x4


'' •A motherboard with at least two free PCIe x16 slots, operating in at least in x8 mode (Nvidia does not support SLI on x4 links). ... ''

http://www.tomshardware.com/reviews/nvidia-sli-faq,4079.html#p2

 

[Omga4000]

amd x-fire only require a slot to be x4 NVidia sli requirement is x8 on the slots that's why even boards that are sli compatible can loose sli capabilities if you add a 3ed card or something that shares the pci-e lanes with the CPU and drops the slots to 8x4x4


'' •A motherboard with at least two free PCIe x16 slots, operating in at least in x8 mode (Nvidia does not support SLI on x4 links). ... ''

http://www.tomshardware.com/reviews/nvidia-sli-faq,4079.html#p2

Well said.
Thank you very much!

 

[Eximo]

I believe Nvidia charges for the privilege, so only boards certified for SLI can do it at all, which only includes the Z class chipsets from Intel and high end boards from AMD. 970/990FX/X370.

 

[junkeymonkey]

thing is with AMD its all run off the chipset so that's not as a limitation as intel where you got to share off the CPU lanes [why AMD chipsets get so much hotter]

''990FX''
Four physical PCIe 2.0 ×16 slots @ x8 electrical which can be combined to create two PCIe 2.0×16 slots @ x16 electrical, one PCIe 2.0×4 slot and two PCIe 2.0×1 slots, the chipset provides a total of 38 PCIe 2.0 lanes and 4 PCIe 2.0 for A-Link Express III solely in the Northbridge

''AMD 970''

One physical PCIe 2.0 ×16 slot, one PCIe 2.0 ×4 slot and two PCIe 2.0 ×1 slots, the chipset provides a total of 22 PCIe 2.0 lanes and 4 PCIe 2.0 for A-Link Express III solely in the Northbridge''

but you see this 970 offers SLI support

'' 2 x PCIe 2.0 x16 slots
- PCI_E2 supports up to PCIe 2.0 x16 speed
- PCI_E4 supports up to PCIe 2.0 x8 speed

https://www.newegg.com/Product/Product.aspx?Item=N82E16813130790

https://en.wikipedia.org/wiki/AMD_900_chipset_series

then from that you can see how each chipset on AMD is limited

this was something I seen with my first intel board and kinda made a mistake , not a biggie but showed me what to look at next time

''The three PCI Express 3.0 x16 slots are controlled by the CPU, with the first slot working at x16 when only one video card is installed, the first two working at x8 when two video cards are installed, and the first working at x8 and the other two working at x4 when three video cards are installed.''

Read more at http://www.hardwaresecrets.com/asrock-z87-extreme6-motherboard/2/#6krlJk94y1DAH0PR.99

so with any intel you got to look at that it don't affect me but it could have ...

now like this board

''The two PCI Express 3.0 x16 slots are controlled by the CPU, with the first slot working at x16 when only one video card is installed, and with both working at x8 when two video cards are installed''

Read more at http://www.hardwaresecrets.com/asus-z87-deluxe-motherboard/2/#R30md7mM5DADeUuR.99

with it only the 2 GPU slots are ''wired to the CPU and no matter what 3ed or 4th slot is used it will all ways be x16 or 8x8

ya, every intel board is ''wired '' different and something to be sure to look at

 

[Omga4000]

thing is with AMD its all run off the chipset so that's not as a limitation as intel where you got to share off the CPU lanes [why AMD chipsets get so much hotter]

How am I to tell that from the board I want to buy?

I was thinking of one of those:
GA-Z170X-Gaming 3
GA-Z170X-UD3
GA-Z270X-UD3

 

[junkeymonkey]

you have to read the slot arrangements in the specs and if unsure download the manual of the board and read anything on it , also some board if you use the M2 slot it can disable another slot ?

like that one board

1 x PCI Express x16 slot, running at x16 (PCIEX16)
* For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
1 x PCI Express x16 slot, running at x8 (PCIEX8)
* The PCIEX8 slot shares bandwidth with the PCIEX16 slot. When the PCIEX8 slot is populated, the PCIEX16 slot will operate at up to x8 mode.
1 x PCI Express x16 slot, running at x4 (PCIEX4)
* The PCIEX4 slot shares bandwidth with the PCIEX1_3 slot. When the PCIEX1_3 slot is populated, the PCIEX4 slot will operate at up to x1 mode.


notice how some of that is worded ''funny''' like this part '' When the PCIEX8 slot is populated, the PCIEX16 slot will operate at up to x8 mode.'

up to x8 mode ??? so it could run at x4 or something ???


see this stuff falls under SUPPORT and today support and quality has taken a far back seat to HYPE and GIMMICKS .. all there worried about is how cool there crazy heatsinks with there brand on them look with all that LED lighting [led lighting is now called a strong selling point ] then on top of that you maybe stranded to the malware called windows 10 to run it all


all you can do is good solid research and homework on any board you want

 

[junkeymonkey]

[ ASRock Z170 OC Formula ]

If that is the case, that gives 12 lanes to M.2 and 8 lanes to PCIe slots, totalling up the 20 PCIe lanes of the chipset before we get to USB 3.1 controllers, networking support or the two extra PCIe 3.0 x1 slots onboard. This means that there is probably some limitation on the combination, or that one of the PCIe 3.0 x4 slots actually comes from the CPU, giving an x8/x4/x4 combination. My specification sheet lists quad-SLI support, although some manufacturers tend to use that to mean dual-GPU graphics cards such as the GTX 690 in two slots. 3-way CFX is also supported, although if these are PCIe 3.0 x4 slots from the chipset, I’m sure they can be used in CrossFire mode anyway


[ Z170 Extreme7 ]

'' but the PCIe layout needs a bit of explaining. The top full length slot is x16, which is then followed by a PCIe 3.0 x4 from the chipset. Then we get a PCIe 3.0 x8 from the CPU, and then a PCIe 3.0 x4 from the CPU as well. This technically gives an x8/x4/x4 arrangement from the processor, but with that chipset based slot in the middle between the main x8/x8, we can get a two-card SLI configuration plus another full length single slot device between them without breaking SLI.''


[GIGABYTE Z170X-Gaming GT ] notice most of the gigs boards reviewed they don't try to explain there slot arrangements ??

For PCIe arrangements, GIGABYTE has used the standard PCIe 3.0 x8/x4/x4 arrangment which affords dual-SLI and tri-CrossFire, although placing a card in the bottom slot will disable SLI due to NVIDIA’s 8-lane requirement per card

its tough to find any review that even try to explain any of it on any boards today

http://www.anandtech.com/show/9485/intel-skylake-z170-motherboards-asrock-asus-gigabyte-msi-ecs-evga-supermicro/3


all you can do is look them up and hope to weed it all out