Not going at full speed?

These are my logs

Session.Name...: oclHashcat
Status.........: Running
Input.Mode.....: Mask (?1?2?2?2?2?2) [6]
Hash.Target....: File (weak.txt)
Hash.Type......: vBulletin > v3.8.5
Time.Started...: Mon Apr 13 06:50:51 2015 (1 hour, 58 mins)
Time.Estimated.: Mon Apr 13 10:31:46 2015 (1 hour, 36 mins)
Speed.GPU.#1...: 334.5 kH/s
Recovered......: 1213/4857 (24.97%) Digests, 1213/4857 (24.97%) Salts


why is it showing 334.5 kh/s when I have the rem radeon 7970?