8gb wordlist for cracking a Rar3

Hi,

I'm fairly new to hashcat. I'm trying to open 2 rar-files. I've read the hash of the rar-file using john the ripper. I've made a wordlist of 8.63 gigabytes big with possible passwords. Now I want to try to use my R9 290 graphics card to speed up the process of comparing hashes.

The hashes look like this:
1.rar:$RAR3$*0*HASH1_HERE*:0::::C:\1.rar
2.rar:$RAR3$*1*HASH2_HERE*0*C:\2.rar*72*33:1::WDC.dat

I've tried this command: hashcat64 -a 0 -m 12500 -o output.txt wordlist.lst

It crashes because there is not enough memory available, although I have 20 gb of memory.

What am I doing wrong?

Thanks for the help!