Overclock.net banner
1 - 10 of 10 Posts

axizor

· Registered
Joined
·
1,430 Posts
Discussion starter · #1 ·
Hi all.

I'm experiencing overheating on a A8-3870k APU I have in my sister's computer I built back in 2012.

It is paired with a MSI A75A-G55 motherboard.

It is cooled by a stock AMD cooler. (please dont stop reading here.)

It began when she told me that her computer would "shut itself off" and the screen went black after some time playing her favorite game, Goat Simulator.

Adding to the details, she has had no problem playing the game for the past several months.

Curious to replicate the problem, I did, and sure enough it did as she described - appearing as a thermal shutdown. After I got Windows to boot back up, I downloaded HWInfo64 and ran a sensor log. Recording temps, I played the game again and it crashed. Upon restarting (I needed to give the CPU some time to cool off), I looked at the logs. The temperatures were high, I believe sub 70c. I do not know the max operating temp, but this site says 72.7c: http://www.cpu-world.com/CPUs/K10/AMD-A8-Series%20A8-3870%20AD3870WNZ43GX.html

Anyways, at this point, I take off the stock heatsink and reseat it, using AS5. I attempted to boot the computer and was able to get into the BIOS once before it began freezing. Checking Hardware Monitor in the MB Bios reported CPU temps of 80c. At this point, I turned the computer off. This was the previous night.

Today, I turned the computer on, went right into bios and checked the Hardware Monitor. CPU idling, I watched the temperature rise from high 30s up to sub 50s before I just turned the computer off.

At this point, I need some help determining if the APU has a problem or it all of a sudden needs some adequate aftermarket cooling. Regardless, this sudden change makes me think it may be hardware related.
 
It is perfectly normal to see temps rise just sitting in the bios on llano chips. For some reason when your idling in the bios the cpu is given full voltage and full load for the entire duration. All of my llano rigs do this and even a Trinity rig I built for a friend.

My recommendation is boot the computer and undervolt the processor in the bios to 1.25V. Most Llano chips have no issues running at this lower voltage. Save and reboot the computer. Now your temps should be more manageable or under control so you can spend more time investigating in the bios.

My hunch is that board is overvolting the processor on its own. My old MSI would put over 1.6V into the cpu when set for 1.475V. Load up cpu-z and see how much voltage is actually going to the cpu.
 
I second Papadope's sentiment. I have a Llano rig that I undervolted to 1.24V and it ran at 2.9ghz no problem (it was an A8-3850.) That alone will lower the temps. Seems like the mobo is pumping a lot of unnecessary voltage into the chip for some reason. The default voltage on my Llano chip was 1.4125 for whatever reason, no idea why AMD played it super-safe with those batches, lol.
 
You might have to open the OC genie sub menu to get it to pop up. I have the A75MA-G55 which is just the microATX of yours. I can check the BIOS when I get home.

My house is full of llanos (5 at last count), and that stock cooler on the a8 with stock bios settings is asking for trouble. My wife has the same CPU and even at stock clocks would get into the 60s easily under load. I just ended up buying a TX3 and using it instead. You don't need anything expensive, but an aftermarket cooler will give you headroom and have less noise. Although undervolting will also work as well (I was just after a bit more speed and OC room on mine).

As for why the stock cooler is suddenly not good enough its hard to say. Fan could be slowly going bad and not spinning fast enough. Could be a bit dusty (though if you pulled it off to put new TIM on I assume you would have dusted it a bit). If you aren't getting a new cooler and don't care about overclocking, then undervolting is the way to go. Depending on your case you might also add a fan to blow more air towards the cpu socket area.
 
Discussion starter · #6 ·
Hey toughacton, would you mind checking the Bios for me? I didn't see any sub menus when I enabled OC Genie and quite honestly, I'm not very familar with MSI boards. I don't want this thing to start OCing itself on me and make things worse.

Edit: there may have been unlocked options available to manipulate when I enabled OC Genie but voltage wasnt one of them. When I go home tonight I'll check back.
 
Quote:
Originally Posted by axizor View Post

Hey toughacton, would you mind checking the Bios for me? I didn't see any sub menus when I enabled OC Genie and quite honestly, I'm not very familar with MSI boards. I don't want this thing to start OCing itself on me and make things worse.
OK so your BIOS looks exactly like my other FM1 board, the A75A-G35 I know for a fact it is voltage locked and no BIOS revisions have changed that. The A75MA-G55 micro ATX board has a different looking BIOS that doesn't have that OC Genie portion. I would have thought a G55 board would have it though. Have you checked the power capability option? What does it do? Your BIOS is a bit different from mine since I don't have the exact board you do and I have mine updated for Win 8 (which if you are running win 8 and haven't changed the BIOS you should look into).

IF you still can't find it you may just have to try different BIOS versions. According to the one BIOS pic I've found CPU voltage should be the first option below Advanced DRAM Configuration and its obviously not there.
 
If all else fails, you can just use K10Stat to change the voltage manually from within Windows. It works just fine for the Llano chips. You can set individual voltage values for each P6 state.
 
You guys are all skipping over the fact that this rig was running just fine and now suddenly has issues.

OP, did you make sure the cpu fan is spinning? It is possible the heat issue is based around a fan failure or slowdown.

suddenly starting to overheat would indicate some sort of hardware failure.

Unless the BIOS was flashed recently and the version flashed is corrupted. That can cause some wicked issues
 
Discussion starter · #10 ·
Hey guys, sorry to abandon thread.

The mb was cpu voltage locked, even tried older bios versions to see if they removed it.

CPU fan/heatsink was working just fine, I even ramped up the RPMs and it didn't help. Basically, the CPU was just getting too much voltage.

I decided to upgrade the rig to a Intel Pentium G3258 and R7 265, both generously overclocked. It's awesome, haha.

As to software based voltage regulation, that may have worked but I much prefer bios >software.

Let's hope my Trinity based server doesn't develop the same problem, also with MSI board.
 
1 - 10 of 10 Posts