G4te_Keep3r

The GTX 1080 Ti I had was the Aero from MSI - also a blowerstyle. 

It ran perfectly fine but then some day gaming performance was literaly cut in half, like my FPS was lowered by ~50% and I was no longer able to watch 4K video files on my PC without it lagging out, making playback at around 5FPS. 

I went through multiple drivers, 3 formats of Windows, so many things, I was never able to fix it. I thought my 1080 Ti was dying. I then took it out of my PC to have a look at it, seeing if there was dust in the fan and honestly on the surface of the card and in the fan, there were like no dust at all, so I of course thought that dust wasn't the issue. Anyhow, I installed it again and took a look at temperatures and GPU temp was fine but the problem was still there, my performance was still cut in half. 

I ended up chatting directly with Nvidia support and they asked me to disassemble the card to look for dust even though I did say to them that GPU temp was fine and there were like no dust on the surface of the card or in the fan but of course, I did was Nvidia said, I disassembled the card and yup, in the middle of the heatsink a big chunk of dust was piling up. I blew it out and assembled the card again and then all performance issues were gone. 

My theory is that this chunk of dust made some sort of heatspot on the PCB that caused something to heavily throttle down. 

So yeah, yours being a blowerstyle too, I'd remove the plastic part so you can see the heatsink and then blow off any dust there might be stuck. 

This.
 
This has actually happened to me on multiple systems for people I fixed. I think the first time I saw this was on a hd 5870 crossfire system. Temps were warm but ok. But something was misbehaving severly. The dude was very hardcore in keeping his system clean but on a random google hunch I decided to take the cards apart.
 
In both 1/4 of the heatsink was blocked by a near identical dustblob. Cleaned that out + repaste and both cards started going well again.

I'd have paid money for Linus to knock the drives in that pyramid he built. 
 
I know we where all thinking something along those lines when that shot came up. 

I had a strong feeling they were going to go 45Drives again for this.
 
I do feel skeptical about their mention of a SLOG device. From my own experience with ZFS a SLOG device won't accelerate write operations with services such as SMB/CIFS or SSH/SFTP. Based on my own research a SLOG accelerates synchronous write which are often seen in VM applications and Databases. Meanwhile file shares are primarily asynchronous which means if the SLOG is used at all it will only be written to at the speed at which the pool itself can accept the data. This means the primary application of the box won't see any benefit from it.
 
I'm open to being told I'm incorrect but this was the answer I came to after a long time of researching SLOG devices. L2ARC should be fine though. ARC is data in ejectable memory though. If the system needs more for other processes it can dump the files. Based on the average size of there's though a L2ARC is probably not a bad idea.