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Just thought I would let anyone know that use's the Rampage edition 10 board of the issue with the M2 and U2 SSD slot on the motherboard.
This board has one issue, when you enable M2 and U2 in bios, because they are linked and can not be switched independently it use's 2 X 8 of the pcie bus resulting in 16x combined even if you only fit a M2 SSD drive. you can not switch off the U2 and even with no drive fitted in the U2 slot it takes 8x pcie bandwidth away.
So even for a simple config of 7800k 28 pcie lane CPU and 1 GPU say 1080 as soon as you fit either M2 or U2 drive 16X of the pcie bus is taken away, so your GPU will only run at 8X pcie. with a 28 lane CPU
other boards you can switch of M2 or U2 so you can maintain X16 on PCIE-1 slot. which if you only ever want to use 1 gpu in your config with a 7800K maintains 16X PCIE on slot 1.
seems asus answer is buy a 40 lane pcie CPU which I find a bit of a get out by asus in the design of the edition 10 board considering its asus's premium board.
just a heads up guys buy a 40 lane CPU if you want everything at full speed. but even with 40 lanes you cant run 2 GPU's in SLI at 16X and have the M2 slot occupied as one of your cards will drop to 8X because the 16X of both M2 and U2 slots will remove 16X of your 40X CPU. if you could enable 1 or the other to only lose 8X pcie then 2 16X GPU and 1 X M2 at 8X makes 40X
Asus an oversight maybe, but for a premium board at premium price someone should have thought of that combined M2 U2 in bios and in the design of the board itself.
This board has one issue, when you enable M2 and U2 in bios, because they are linked and can not be switched independently it use's 2 X 8 of the pcie bus resulting in 16x combined even if you only fit a M2 SSD drive. you can not switch off the U2 and even with no drive fitted in the U2 slot it takes 8x pcie bandwidth away.
So even for a simple config of 7800k 28 pcie lane CPU and 1 GPU say 1080 as soon as you fit either M2 or U2 drive 16X of the pcie bus is taken away, so your GPU will only run at 8X pcie. with a 28 lane CPU
other boards you can switch of M2 or U2 so you can maintain X16 on PCIE-1 slot. which if you only ever want to use 1 gpu in your config with a 7800K maintains 16X PCIE on slot 1.
seems asus answer is buy a 40 lane pcie CPU which I find a bit of a get out by asus in the design of the edition 10 board considering its asus's premium board.
just a heads up guys buy a 40 lane CPU if you want everything at full speed. but even with 40 lanes you cant run 2 GPU's in SLI at 16X and have the M2 slot occupied as one of your cards will drop to 8X because the 16X of both M2 and U2 slots will remove 16X of your 40X CPU. if you could enable 1 or the other to only lose 8X pcie then 2 16X GPU and 1 X M2 at 8X makes 40X
Asus an oversight maybe, but for a premium board at premium price someone should have thought of that combined M2 U2 in bios and in the design of the board itself.
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