So ... Reference AMD 6800XT does fit in Sliger SM550. Kinda ...
For a start I should apologize - I don't have enough pictures to show the whole process and the issues. With my two littles you either act quickly or you are out of time. I will try to be detailed enough with words.
The short answer is YES - Reference AMD 6800XT fits in Sliger SM550. It fits even without any modifications, but you are better off with 1 particular.
Installations issues:
- The top stud insert does not allow fitting the card at all. In order to install the card, you should remove the top panel and also unscrew the PCI-E holder. Then you insert the card from the top, fit the PCI-E slot onto the card and then position them both properly in order to screw the PCI-E holder again.
- The card fits JUST below the stud insert, however the bottom rivet holding the insert pushes the card towards the internal of the case. As a result of this the card sits at an angle you have the following issues:
- The mount at the rear of the case (don't know it's name actually) does not lay flat and the screw holes are off - you can't screw the holder to the case
- As a consequence of the above, mounting the PSU cable plate is almost impossible. One screw gets it, but the other not. You can fit both but with a lot of force and screwed just a little
- Because of the angle the GPU sits, the clearance between the back of the GPU and the spine of the case, where the 8pin connectors are, is (even) smaller. Any less bending cables (in my case, custom) push the GPU more from that point outwards so it does end up sticking out of the case and side panel cannot be mounted.
- The top panel needs a lot of force to get in and you can only screw it at the back - the front holes are misaligned.
- Inserting the front plate is quite hard and it is misaligned
- There is obviously a lot of force distributed through the case and the GPU because of the bend
- The HDMI slot (which is the top one) might be blocked by the case
- As I said - custom cables are out of question without modding anything. Granted, I have the most stiff scenario - MDPC-X sleeving + 16AWG wires. Probably stock Corsair SF cables will fit
All of the above can be (almost) solved by removing the bottom rivet of the insert. But don't do it like me - I sanded it off (almost) while the rest of the HW was in the case. Obviously flying metal dust is a bad idea ... Fortunately, I type from this machine now ...
After some sanding (and cutting with the pliers), it looks like this. Note that it is not flush and it might be still touching the GPU, but I couldn't do more give the circumstances:
This solved almost all issues - the case assembles properly, I was able to screw the back mount on the case (note that because of the not perfectly flush rivet, the screw hole was a little off, but with some force, all aligned properly). I was able to mount the PSU cable as well a close the top panel properly.
The issue with the PCI cables was also almost solved - I only had to remove the cable combs and spread the wires next to each other. Due to the stiffness they still push the GPU a bit, but not enough - the GPU does not touch the side panel:
As you can see by the shadows, I pulled it off. The card really JUST fits (49.75mm spec VS 50mm clearance) but this rivet should go away.
Will I do it again? Yes - the feeling when you power up the system is nice.
Sadly, as I said, I didn't have time for fancy pictures, so here is one less-fancy:
Didn't have time to do thermals and stuff, but single run of 3DMark reports around 2200mhz core with the case on the GPU side next to a wall.
P.S. In case someone wonders - photos were taken with last years flagship Note 10+. Since my Note 4, 5 years ago, cameras didn't really move.
P.S.S. Will re-read the post for typos and stuff tomorrow ...