PCIE Lanes, NVME, SLI, oh my!

S

ScArE2100

Limp Gawd
Joined
Jan 22, 2004
Messages
376
Brushing off my posti'n shoes, it's been a while :)

I have an Asus X99-Deluxe and an i7 5820k. My question is about PCI express lanes. Right now I have:

16x GTX 980
4x Intel 750 SSD (NVME)

That means I'm using 20 of 28 lanes on my CPU.

I just got a new Monitor (4K) and I'm getting about ~45 FPS in the game I play most. I'm considering getting a 2nd GTX 980 for SLI to push me up over 60fps (to match the monitor).

I believe if I got a 2nd GTX 980 with my current configuration it would look like this:

8x GTX 980
8x GTX 980
4x Intel 750 SSD (NVME)

Still 20 of 28 lanes.

My questions:

1) will limiting the GPUs to 8 PCI Express lanes cause problems? If so is it worth the money to go up to the 5390k and sell the 5280k for the 12 extra PCI Express lanes?

2) If I do go SLI, which slots in my X99-deluxe should I use for each video card + the nvme SSD?

Thanks for your help!
 
Looking at the motherboard manual I found these:

http://imgur.com/BKTa2A9,yNZCLsO

So it looks like w/ a 28 lane CPU I can use slots 1, 2 and 4, but then in the 2nd image it recommends putting the gpus in 1 and 4 in SLI mode. This means the SSD would be between the two graphics cards. Seems weird, but I guess it's fine?

So assuming I did that:

Slot 1: 16x GTX 980
Slot 2: 4x intel 750 ssd
Slot 4: 8x GTX 980

For a total of 28/28 lanes. Does make sense? or should it be:

Slot 1: 16x GTX 980
Slot 2: 8x GTX 980
Slot 4: 4x intel 750 ssd

Does this make sense? Thanks!
 
I would try the 980s in slots 1 and 3 with the SSD in slot 5, see how it goes, then change things around if necessary.
 
I would go with what the manual says dude. They designed this motherboard for ENTHUSIASTS LIKE YOU and they are well aware how popular the 5820k is, so obviously they know what they are doing. You don't need to second-guess the optimal board configuration here :D

They reserve 16x for the master card, and 8x for the slave card, and a 4x for a card between those. It's actually quite common to separate the SLI video card slots like that, as it allows for taller coolers and plenty of airflow.

Actually, I don't think a slot with 4x bandwidth will support SLI - Nvidia's drivers will lock it out unless all the GPU slots have at least 8x bandwidth.

You do not need an 8x slot for an SSD, but your GPU will certainly benefit.
 
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I'm going to try it out Friday and report back with results. My first plan is to try them seperated with the SSD in the middle which should provide better overall cooling since the GPUs will have more room to breathe.

Thanks,
Marshall
 
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