OK, I've now tried it 3 times and am convinced it is not a RAM problem:
I boot my new PC from USB-drive and automatically Memtest86+ (4.20) is started; I decided to let it run for a night and switch my monitor off.
When I come back to check the results, I switch my monitor on:
- Memtest86+ hangs, wallclock timer is frozen
- No errors in memory reported
- The '+' in 'Memtest86+' still flashes, as does the cursor, so it is not a frozen display
- The time the wallclock timer displays matches the runtime since I started testing. So when I started at 11:00pm and check the next morning on 06:00am, it will show a wallclock time of 7 hours. Next time I only ran for 3 hours (frozen wallclock shows 3 hours) and I just ran Memtest86+ for over 20 hours - and the wallclock was frozen on 20 hours. Oh, and my RAM is without problems - at least Memtest86+ never reported issues.
So to me it seems that switching my monitor on causes Memtest86+ to hang. Bug report!
Motherboard: Intel DH67GD
CPU: Intel Core i5 2400
RAM: 4 x 2GB Kingston valueram 1333 DDR3
Storage: Samsung 830 256GB SSD
No videocard (using the CPU video)
Monitor: Dell U2410 connected via DVI on DVI-1 input
In case it is relevant: I have no problems with this PC, just wanted to be sure my memory was OK. Only problem I have is that occasionally it hangs during boot (Windows logo freezes at random times).
I've used two USB flashdrives: one was already bootable and I replaced the old memtest86+ with a new precompiled memtest86+ binary; the other I flashed with the auto installer for flashdrives. Both have 4.20 now.
If I can help out solving this bug by doing tests or providing information - please let me know.
I start Memtest86+, immediately press F1. Wait until the wall clock reaches 10 seconds, then switch off monitor. Wait another 10 seconds, switch on monitor. After some power-on delay, I see the wall clock frozen at about 30 seconds.
And: start Memtest86+, press 'c' for config menu. Can view SPD information without problems. Then switch off/on monitor - and Memtest86+ is frozen again (except for the blinking '+' in the title line).