GPU-Z sometimes reports blank value "-" for GPU temp in log file, how to interpret this?

[750ti_Enjoyer]

I am trying to troubleshoot an intermittent crashing issue. I'd like to know what my GPU temp is right before a crash, so I am using the log function of GPU-Z. After the last crash, I looked at the log file, and GPU temp was "-" for the minute and a half before my crash. It was normal for the time stamps before this, at a steady 25 - 30 C. No ramp up or crazy fluctuations or anything. This was yesterday. Booted up today, and the log now only displays "-" for all times today. I'm not sure if I'm missing something, or if this may be a symptom that could explain my difficulties. Any help would be appreciated. I have attached a section of my log file if that is helpful.

 

[W1zzard]

Which GPU? The - is either "GPU sleeping" or "no usable data received"

 

[750ti_Enjoyer]

I was trying to respond right away and then my computer crashed again, whoops.

My GPU is a 750ti on a gigabyte board. The measurement in question is "GPU Temperature [°C]". Hope that clarifies, please let me know if not. I can't think of a reason why no GPU temp data would be received.

 

[P4-630]

Booted up today, and the log now only displays "-" for all times today.

Using hibernate or fast startup? If so , what happens when you disable those.

 

[750ti_Enjoyer]

Using hibernate or fast startup? If so , what happens when you disable those.

After a full shutdown and startup.