Pluscat vRAM usage study
Ello there.

I've did something similar for EGB, now it's time to do this for pluscat.
Command line:
cudaHashcat-plus64 -m 0 -n 8 -a 6 -r "rules.txt" --markov-hcstat hashcat.hcstat %hashlist% "leaked.txt" ?l?l?l?l
Now, I've used hybrid + mask for a reason. Atom told me that this mode uses to most vRAM, which is a good thing for a worst-case scenario.
The rules.txt contain original InsidePro rules, which can be found in the pluscat archive.
Leaked.txt is the RockU wordlist.

1 hash      =   93 MB
10 hashes   =   93 MB
100 hashes  =   93 MB
1K hashes   =   93 MB
10K hashes  =   94 MB
100K hashes =  128 MB
1M hashes   =  204 MB
10M hashes  =  930 MB
15M hashes  = 1311 MB
16M hashes  = fail

So, the limit for my GTX 480 with 1.5GB of vRAM is 15M MD5 hashes.
Cant say if the memory usage would be the same for AMD gpus,
Also, vRAM usage will grow with the growth of hash length.
If I could load 15M MD5 hashes, that doesn't mean I am able to load 15M blowfish hashes, for example.

Atom informed me that pluscat uses 80 bytes per any hash, and 108 bytes per salt.
So, blowfish hashes would use the same amount of vRAM if they were unsalted (this means since MD5 is unsalted, it doesn't use the 108 bytes / salt, but it pads the 64 bytes per hash with 0s).

I used MSI Afterburner to measure vRAM usage.