Bad RAM symptoms?

[Donny Bahama]

Can bad RAM cause the system temperature to spike? My PC has shut down twice in the last couple of days. Each time, the screen just suddenly went black and when I started back up and checked the CPU temp, it was very high. I ran Memtest overnight and came up with 1600 errors on 5 passes (temps stayed nice and cool), but was the RAM damaged by the heat? Or did the RAM cause the heat?

This is a fairly new build, with an Asrock FM2A85X, A10-5800K (running at 4.4GHz and cooled by a Zalman CNPS9500A), and G.Skill Sniper DDR3-2133 RAM. After building it, I ran Prime95 for over 24 hours. The system never broke a sweat.

 

[smeezekitty]

You likely have two problems. Insufficient cooling and bad memory.
Although you might try backing off on the OC and see how it works out.

 

[Donny Bahama]

I really don't think it's insufficient cooling. The Zalman cooler is highly rated, and I've got multiple case fans and good airflow. I monitored temps while running Prime95 and everything stayed nice & cool no matter how hard I pushed.

In fact, nice & cool is the status quo since the initial build (except for these weird episodes). Since this started happening, I've tried to keep my eye on Speedfan in the tray. At the moment, CPU is 89F, System is 82F and HDDs are at 79F and 75F. (GPU reports 27F but somehow I doubt that's accurate.) The machine stay that way for hours - even days - under varying loads. (E.g. tons of tabs open in Firefox while simultaneously working on some really huge images in Paint.net.) All the while, I'm seeing CPU temps in the high 80s/low 90s. Then, next thing I know, my monitors go black and the system goes into (what I assume is) some sort of protection mode. I immediately restart and check HW Monitor in BIOS and the CPU temp is scary high. No CPU fan failure - I (currently) have it maxed out and it's the loudest thing in the system. I'm sitting 2 feet away; I'd hear it if it stopped.

So, setting cooling aside, what can cause these sudden CPU temp spikes? I know for sure the RAM is bad (unless Memtest has it wrong) - and the machine never got hot during the memory testing. (AFAIK - it ran overnight and was cool (low 80s) when I checked it the next morning.) Replacement RAM is on its way. I guess I'll know soon enough whether the RAM is cause or symptom.

Would love to hear from anyone else who has experienced similar symptoms.

 

[smeezekitty]

A shutdown or reboot is the common way for the motherboard to handle a CPU overheat condition.

If the memtest shows bad, most likely it is caused by RAM but occasionally a bad motherboard or CPU or unstable OC can cause it.

I would get some new RAM and test again. If it persists than back off on your OC.

 

[Donny Bahama]

Got the new RAM, installed it, no recurrences since.