CPU Clocking Down (Throttling) when Stress Testing

rajadog

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Hey there, I am having a problem with my FX-8350 Throttling down whenever I run a stress test (Prime 95, AMD Overdrive). It usually runs fine for about 5-7 mins, but than the clockspeed will clock down to 3.4 (17x Multiplier, ~200x bus). I would assume it would be VRM overheating, but my Voltage is steady at 1.4125. It does not decrease. Only my Multiplier (and thus, clock speed have decreased, so I don't think it's an overheating issue.

So after running Prime 95 for a few minutes, my CPU Multiplier drops to 17x which gives me a clock speed of 3.4 ghz. This doesn't go back to the normal 4.0 ghz until I restart.

Please note, I am not overclocked, and my CPU temps are well under 40c during Prime 95 testing.

I have tried changing the power settings in the DIGI+ power control in the Bios, but nothing has changed.

apot.png




I also have every single power setting off I could think of, including Cool And Quiet, and windows power settings set to high.

Here is what my AMD overdrive looks like after testing.

auqq.png




Full Specs

Fx-8350 @ 4.0ghz (Stock)
Asus m5a99x Evo r2.0 am3+ amd 990x
8 GB DDR3 @ 1333 MHZ (Can't seem to get it to boot with much more)
Radeon 6870
EVGA 600 Watt PSU


Any Help would be appreciated.

Thanks
 

rajadog

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Thanks for the guide.

I don't believe my chip is one of the good batches. I had to volt to 1.43 to get stable at 4.6 ghz before. The only time it wasn't stable was when I stress tested, and it would clock down.

The reason it was volted at 1.4 at stock was because AMD Overdrive does that when it stress/tunes.

I updated the bios, but I am still getting the issues. I really am confused.

I doesn't seem to be VRM overheating since the Voltages aren't changing and the Chip certainly isn't overheating, under 45c when overclocked.

Are there any Bios or Windows settings that would cause my CPU to throttle, but not the voltage?

Thanks!
 
Yeah, I think I'm going to be thermally limited to 4.4, having to bump the voltage a whole lot to hit 4.5. Just not worth it IMO. Which indicates that I also have a 'bad' chip. I'm on a pretty budget mobo anyway.

I honestly don't know. If you've followed the guide to the T then I'm not sure what else to suggest. The only things I could say, not being an OCing vet, is that it would be voltage/temp related but it seems that isn't the case.

I assume you've turned off C6 etc (I know you said you turned off CnQ)? Have you tried disabling HPC mode? Or manually setting CPU/NB voltage to 1.25v-1.3v?
 

rajadog

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I have C6 and HPC both off. I am a bit confused as to what HPC mode does. From what I've read, it prevents the CPU from throttling itself? Shouldn't I want to turn it on?

Also, I got it stable at 4.3ghz @ 1.31 volts. So it seems that it doesn't like high voltages. So do you think this is just a bad chip? Or should I try the HPC mode?

Thanks!
 


Try HPC by all means, it just causes problems on some motherboards but is beneficial on most.
 

rajadog

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Ok, I turned HPC on, and changed all my Bios settings to match the one in the guide you linked, and no effect. It still throttles.

Also, I have a question about the CPU Manual Voltage and the VID in core temp. No matter what I set my CPU Manual Voltage to in my Bios, core temp, and AMD Overdrive always read 1.3175. If I have an overclock, I have to manually change the CPU VID in AMD Overdrive to get it not to freeze within minutes of start up. Am I missing something here? What am I doing wrong?

Edit: I also noticed that my NV VID is at 1.16, instead of the 1.25 which I set it at. Why does it not stick when I change it in the bios?

Thanks
 

rajadog

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It seems to be throttling worse now. It is throtling now at 1.325 Volts @ 4.6ghz.

Im going to be quite mad if I find out it's my motherboard overheating again. I just had to upgrade my motherboard because my last board (770) couldn't even handle stock temps. I did extensive research, and found the one I bought had the least amount of complaints about throttling (in fact, I didn't find a single one). I am not going to get a new motherboard.

I haven't seen anyone else having issues with this board, in fact, i've only heard of people having great success with it.

http://forums.overclockers.co.uk/showpost.php?p=23968491&postcount=6

My VRM is hot to the touch though, can only touch it for about 10 seconds without almost burning myself.
 
The max of the CPU on the core should be 62C. The socket should be 70-72C.

In that image you have circled the Socket temp, which is a little toasty but you won't see temps that high in normal use. However it probably is throttling. My own reaches 74C on the socket @ 4.4, I think I'm just above 1.32v. Your core temp (shouldnt go above 62C) is located under the subheading "AMD FX-8350".

Are you using an aftermarket cooler? I don't think your motherboard is the problem.

 

rajadog

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I am using the Corsair H55. Also, I clocked down to 4.4 @ 1.31vid and 1.35v in bios. It reaches a max of 73c socket, 49c core, and it still throttled.