The max supported CPU for your system is the 8700K or 8086K.  If you have air/fan cooling for the CPU, the max CPU would be 8700, unless you upgrade to liquid cooling. 

  Any GPU will be compatible, the problem is the physical dimensions.  No 3 fan GPU will fit in this system.  Many double fan GPUs will fit, many will not, so you need to measure it first.  However, due to the small form factor case, double fan GPUs are not recommended for the Aurora because they are more likely to cause overheating (they recycle hot air into the case and there's little air movement as it is). 

Dell only sells the Aurora with single fan blower style GPUs.  If you're looking at the RTX series, that would be something like an Asus Turbo, MSI aero, or PNY blower. These will all fit. 

Forgot to mention that you would need the 850W PSU for the 2080 super. If you have the base 460W PSU, you'd need to upgrade that first. 

Hi,

    I am not sure my question makes sense but still want to post here because I guess there are people thinking about it too.

    Is it possible R7 is compatible with Nvidia's upcoming 30series graphics card? Maybe no need to be compatible with the flagship but just any one of that series.

    Thanks,

Of course, why wouldn't it be?  The limitations would be size (physical) and PSU (power). 

Inb4 CPU chokes RTX 3090.

what is the max length gpu that can fit into the R7? is it 11 inches or 10.6"? If you have a CPU with liquid cooling is it okay to have a dual fan gpu in the R7?