MSI X99A GAMING 7 (3-WAY SLI). Does it support 4 VGA cards?

JoeFares

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I just purchased an MSI X99A Gaming 7 motherboard as I was under the impression it supports 4 VGA cards.

However, I got extremely confused when I read that it supports 3-WAY SLI.. Does this mean that I can only connect 3 video cards? What confuses me is that the motherboard has 4 PCI Express slots.

I am sure my question would sound extremely dumb to all you experts. But for me, I am not quite experienced with hardware as I only used laptops during the past 10 years and would appreciate if someone is kind enough to assist me.

PS: I do not need SLI as I need all 4 video cards to work individually. I am creating this as a cryptocurrency mining rig which is why SLI is not needed (Actually having all VGAs in SLI is a negative factor). I already purchased 3 Nvidia GTX 970 and wanted to double check before buying the 4th one. (Can't believe the computer sales people in my country have no idea how many cards this supports,.. And worst of all, they don't accept returns)
 
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Solution

Gillerer

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As it says in the specifications on MSI's page, only 3 slots can be used at any one time. Which ones, depends on whether your CPU has 28 or 40 PCIe lanes. Many motherboard vendors have "extra" slots on their X99 motherboards - I'd guess to ease the routing for the two PCIe lane configurations.
 
look at this board and see how the slots are apart to take 4 cards where yours the bottom slot is so close to the 3ed slot and causes that card to cover it up

http://www.newegg.com/Product/Product.aspx?Item=N82E16813128829&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-PCPartPicker,%20LLC-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
 

Gillerer

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In OP's motherboard the bottom slots can be next to each other because the wiring doesn't allow both to be used a the same time anyways. How many PCIe devices are supported is not just a matter of slot spacing.
 
The four 16x slots all use bandwidth directly from the CPU. This configuration changes if you are using a 28-Lane processor where slot #7 is disabled completely. Slot #2 is the typical primary graphics card slot and will use 16x lanes of bandwidth provided you don’t populate slot #6. Slot #4 is the second primary slot and will always have 16x lanes of bandwidth regardless. Overall I found the layout to be very logical and a good use of space.

For best video performance you will want to populate slots #2 and #4 with video cards. For proper triple card configurations you'll populate slots #2, #4 and #6. Slot #7 is really an extra slot on the X99A Gaming 7 since the only time it can be used is with a 40-lane processor which isn’t a bad thing and actually gave us an almost identical Multi GPU Index score for both processor platforms.

http://www.hardwareasylum.com/reviews/motherboards/msi_x99_gaming-7/page5.aspx


as said sad thig is the 3ed card covers the slot and renenders it useless and why its call 3way out side of that is still a full pci-e slot [depending on chip as we know ]
 

Gillerer

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Why would MSI misrepresent the PCIe capabilities of their own motherboard - saying it can only support 3-way function if it can support 4-way? Slot spacing doesn't enter into how many GPUs a motherboard can support - after all, there are single-slot GPUs.

Again, from their product info:

4 x PCIe 3.0 x16 slots, support up to 3-way mode

- 1-way mode: x16/ x0/ x0/ x0
- 2-way mode: x16/ x16/ x0/ x0*, 16/ x8/ x0/ x0**
- 3-way mode: x16/ x16/ x0/ x8*, x8/ x8/ x8/ x0**

* For the CPU that supports 40 PCIe lanes
** For the CPU that supports 28 PCIe lanes

There is no mention of 4-way mode.
 
says so in the specs???

''Multi-GPU: Quad NVIDIA SLI & AMD CrossFire Support'' unless quad now means 3 ??

its that the slot cant be used cause the 3ed card covers / blocks it use out side of that its full wired pci-e slot

don't matter overall the slot is covered / blocked so that's the end result I don't guess your planning to go back to the thin single slot cards from the 90's on it ???

what worthy card today in not a 2 slot or a bit more in size anyway ??


looking at another board like it this maybe the reason why its slots are listed as 3 way as you see

''In both cases, the last slot (PCIEX16_4) shares bandwidh with the on-board M.2 slot; if this M.2 slot is used, this PCI Express 3.0 x16 slot is disabled.''
 
''Quad may refer to: An abbreviation for "quadruple" or four in many contexts,''

that don't mean 2 quad means 4 in the English language like a quad-runner is a 4-wheeler not a 2 or 3 wheeler


I added this above and maybe why it speced that way ??

looking at another board like it this maybe the reason why its slots are listed as 3 way as you see

''In both cases, the last slot (PCIEX16_4) shares bandwidh with the on-board M.2 slot; if this M.2 slot is used, this PCI Express 3.0 x16 slot is disabled.''

to me anyway if getting a ''X'' board with out a plx chip to me in no point
 

Gillerer

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2 x 2 = 4. Two dual-GPU cards have four GPUs in total, so it's still Quad-SLI and works (as far as SLI goes) just like four separate cards.

If the limitation were due to M.2 slot, I think they'd say so.

There are plenty of uses for an extra PCIe expansion slot even if the device in it could only be 1 slot thick. I very much doubt MSI would deliberately not want purchases from people interested in using such devices. (Examples: PCIe SSDs, 10Gb network adapters, RAID controllers, single-slot low-end professional GPUs with 4 x MiniDP each: some professionals just need the maximum number of high resolution displays without being considered with 3D performance.)
 
''If the limitation were due to M.2 slot, I think they'd say so.''

well I don't see any fact or straight forward info on his board anyway just a lot of hype and unsure of's and why you look hard before you leap

bottom line is the 3ed card covers the slot so you cant use it anyway regardless