oclHashcat v1.33 speed drop

Hello, is that normal?..


===============================CudaHashcat 1.31:
Session.Name...: cudaHashcat
Status.........: Exhausted
Input.Base.....: Mask (?a?a?a?a) [4]
Input.Mod......: File (example.dict)
Hash.Target....: File (example0.hash)
Hash.Type......: MD5
Time.Started...: 0 secs
Time.Estimated.: 0 secs
Speed.GPU.#1...: 41186.6 kH/s
Recovered......: 2190/6494 (33.72%) Digests, 0/1 (0.00%) Salts
Progress.......: 136302297088/136302297088 (100.00%)
Skipped........: 0/136302297088 (0.00%)
Rejected.......: 0/136302297088 (0.00%)
HWMon.GPU.#1...: -1% Util, 65c Temp, -1% Fan

Started: Thu Feb 19 22:09:59 2015
Stopped: Thu Feb 19 22:24:07 2015 <---- = 14mins


===============================CudaHashcat 1.33:

Session.Name...: cudaHashcat
Status.........: Exhausted
Input.Left.....: Mask (?a?a?a?a) [4]
Input.Right....: File (example.dict)
Hash.Target....: File (example0.hash)
Hash.Type......: MD5
Time.Started...: Tue Feb 24 23:59:16 2015 (27 mins, 22 secs)
Time.Estimated.: 0 secs
Speed.GPU.#1...: 83355.9 kH/s <--- wut???
Recovered......: 2190/6494 (33.72%) Digests, 0/1 (0.00%) Salts
Progress.......: 136302297088/136302297088 (100.00%)
Skipped........: 0/136302297088 (0.00%)
Rejected.......: 0/136302297088 (0.00%)
HWMon.GPU.#1...: -1% Util, 71c Temp, -1% Fan

Started: Tue Feb 24 23:59:16 2015
Stopped: Wed Feb 25 00:26:49 2015 <---- = 27mins


??

NVIDIA GeForce GT 630M, CUDA 6.5.14, Nvidia 346.35,