Computer re-booting is almost always a hardware issue. My first guess is that the CPU is overheating, and that the cooling system isn't working properly.
Thanks for the responses.
I have already installed HWMonitor when dj_page suggested it may be due to overheating yesterday.
Tried to insert a print sceeen but file was too big.
The CPU package is running at 62°C
the 4 cores vary from 61,62,64,54
I don't know if this is hot or normal.
Once I get into Lightroom I have no way of telling what the temps are as the second I generate a 1:1 preview the computer reboots.
All three case fans and CPU fan are running.
Don't know what else I can check.
The case is a mid-tower Antec with lots of space and well designed ventilation.
Currently I'm using the Intel graphics display built into the motherboard. Have a new graphics card coming because I suspect that the added load of the video onto the CPU may be causing the issue. What do you all think?
My cores are 35-40 before computing previews, and during that they go up to 40-60 but mostly in the low 50s. This is the continuously varying instantaneous core temperature.
Do Standard Previews make it reboot?
Does it reboot if you Export to full-sized JPGs, which is similar to what previews are.
Have you checked your HD for errors?
Can you do a memory test during boot up -- some special startup mode by pressing a key?
62 C is way too high
Thanks for the replies I'll have to check and see if the CPU fan needs to be re-seated.
And let you know what I find.
Thanks again for your insights.
After doing all sorts of stress tests on the CPU I couldn't find a real cause because heat wasn't the issue. While the CPU ran on the hot side I was able to have it run over 7 minutes using HeavyLoad running everything BUT the CPU load and the temps would rise to over 90 C and still run without a problem. I then waited for all the temps to return to 30 C (idle temp) and would just apply a CPU load. The moment I clicked the start button the computer rebooted with the temps still at 30 C. So I took the same model CPU from my older computer that ran at 3.5 GHz (instead of 4.0 GHz) and installed it in the problem computer. The 3.5 chip ran without a problem so I called Newegg and they are replacing the CPU which will take about 10 days to turn around since I was returning it after the 30 day return period.
I do not think any of the answers around this topic are right. There is something very wrong with LR 5.6. Why do I say this? Look around the posts - there is a pattern. Add this. My wife and I both have CC plans. I have two machines running CC (inc LR5.6). My wife has one. All three installs are going through 'corrupt catalogue / will atemp to fix on restart / close ....... repeat.
We have done all the things you all have............no joy.
Come on Adobe!
Once the computer spontaneously reboots, something is likely corrupted with the catalog and/or preview cache and trying to open the catalog on another computer isn’t going to change that. I suspect LR 5.6 (or maybe 5.5) is the first version to actually pop up an error message when the preview catalog is corrupt, so just because the messages are all references LR 5.6, doesn’t mean the problem started with 5.6, just that 5.6 is the first version to notify about the issue.
Have you deleted the preview cache folder?
Create a new, empty catalog and import everything from the old catalog into it.
You have a different problem, SussexJohn. Of course none of the solutions discussed work for you.
Ssprengel has the answer, delete your preview cache.