AMD FX8350 - Which temprature do I trust?

Bullet5 · 7 Jun 2013 at 08:40

Hello everyone. I'm in search of a little wisdom after having spent hours trawling the internet to find few answers. So if any of my queries sound a bit stupid... please don't go too hard on me.

Introduction (of sorts)

Over the past few months I've been playing Planetside 2 on my main system, and my frame rate hasn't been what you'd call perfect. In little battles they would be around 30-40fps, however as soon as the population in the area around me exceeded ~30, my frames would take a huge hit and I'd end up maxing out at about 10fps. In these large battles the frames would dip and dive hugely and I'd end up running around 3-4fps. Not enjoyable.

So to combat this I've installed some new parts:
AMD FX8350,
Corsair H80I,
OCZ Vertex 3 128gb.

These have replaced the following:
AMD Phenom II x4 955,
Generic stock CPU cooler,
Western Digital HDD.

Now the game is running silky smooth, and in large battles I never dip below about 35. Problem solved? Not quite I'm affraid.

The problem

I like to monitor my CPU temps, and did have a mild overclock on the old Phenom, however I am having difficulty working out the FX's temps. Programs such as CoreTemp, HWmonitor, AMD Overdrive and CorsairLink are not registering the correct tempratures.

Now from what I can work out from my research is that these CPU's don't register idle tempratures correctly, or to put it another way, are difficult to find, as I am sat in a room with an ambient temprature of 22C, yet all of these programs list my CPU temprature to be 14C. If I run Prime95 for 10 minutes the maximum temp according the the above programs is no more than 32C. Which even though it would be nice, I'm not 100% sure this is correct. I have noticed that when on load, the cpu temps stop jumping all over, and instead progress steadily.

If I enter Bios when I start up my PC, the temp is usually between 32 and 39C. :confused:

Another sensor I've been watching in HWmonitor is what I believe to be the socket temp (TMPIN0). This on idle sits around 35C and maxes at 43C after 10 minutes of Prime.

If I place a thermometer over the exhaust fan on top of my case, it reads 26C at idle and about 30C on load.

The question

Should I disregard the "cpu" temps and just go by what the socket temp is at, bearing in mind that I am only going to push for a slight overclock (perhaps 4.6-4.8Ghz).

I'm very sorry for the length of my post, but I felt more detail would be better than painting a vague picture.

Many thanks,
Tom.

P.S. I've listed my system specs below along with a screenshot.

AMD FX8350 (clocked at 4.1 Ghz),
16GB of Corsair Vengeance Ram (clocked at 1600Mhz),
1Gb Asus Geforce GTX560TI,
OCZ Vertex 3 128GB SSD (Primary drive),
Western Digital 1TB HHD (Secondary drive),
MSI 990XA-GD55 Motherboard,
Corsair H80i CPU cooler.

Cooling wise, I'm using a pretty generic case, but modified it so I have the following fans:

Front: 9.2cm Arctic Cooling (Intake),
Back: 9.2cm Arctic Cooling (Exhaust),
Side: 2x 12cm Arctic Cooling (Intake),
Top: H80I radiator, with two 12cm fans in push pull (Exhaust).

Smoogels · 7 Jun 2013 at 08:53

It's normal. On HWMonitor I look at the package temperature for my 8350. Not sure if it's correct or not, but it's the same as the socket temp the Sabertooth motherboard says.

If I recall correctly the socket temperature will be slightly hotter than the CPU. 40C ish is absolutely fine for BIO temps whatever processor you have. My 8350 is 40C and a my brothers 3570K is about 38C.

Hagar · 7 Jun 2013 at 09:10

Under load the core temps will be within a few degrees of the package (CPU) temp and I would monitor both. At idle the core temps do not read well and can be several degrees below ambient however the CPU temp should be accurate. I idle at about 30C at the moment and prime at about 60C (4.6GHz) Generally under gaming loads it is about 45-50C. HWmonitor seems accurate for me.

Bullet5 · 7 Jun 2013 at 09:36

Thankyou for the speedy replies.

That would tie in nicely with the reading I did smoogles, as it's not directly cooled it would be a couple of degrees warmer, but would still be a good reflection on the processors temp.

So as an answer to this question I would be wise to keep a steady eye on both values, but use the socket temp as an upper limit when OC'ing this processor?

I just can't believe that the package temp on load is so low. As soon as I begin Prime the temps jump up to a more reasonable figure (than say 14) and then increase at a steady rate, starting at ~26C. Would this be a good indicator for idle temp? If not does anyone have any suggestions as to how to work out a decent idle temp?

Thanks for the input so far!
Tom.

Hagar · 7 Jun 2013 at 09:50

Bullet5 said:
Thankyou for the speedy replies.

I just can't believe that the package temp on load is so low. As soon as I begin Prime the temps jump up to a more reasonable figure (than say 14) and then increase at a steady rate, starting at ~26C. Would this be a good indicator for idle temp? If not does anyone have any suggestions as to how to work out a decent idle temp?

Thanks for the input so far!
Tom.

If you have a very good cooler and good ventilation or airflow, 26C is a reasonable if low idle, I'd assume a delta of ~10C above ambient. I would expect about 30C at this time of year.

Bullet5 · 7 Jun 2013 at 13:43

Roger that. I'll take the readings with a pinch of salt for the time being.

Time to go bury myself in the fx overclocking topics.

Thanks again,
Tom.

Resident · 7 Jun 2013 at 15:28

With my AMD I've found the core temps reported by the CPU itself under-read by about 19°c. In software such as HW Monitor it's possible to set an offset value for the sensors eg my core sensors have an offset of 'sensor reading' +19°c.

scottmorley · 7 Jun 2013 at 17:38

i have an [email protected] with a corsair h80i and idle is normally around the 20's and in games i don't actually monitor the temps because i only have the one monitor and don't like tabbing out. but after a while of playing battlefield 3 my max reached temp is normally 55-57degrees which i think is to hot. but i'm not sure if thats what it's actually running at or whether it's just a temperature jump/spike?

thats with core temp and corsair link.
hope it helps

Bullet5 · 8 Jun 2013 at 19:24

I've had a look at offsetting the readings, but in all honesty I've no idea what the true temprature is so I could be resetting it way off.

To tell you the truth, I'd expect the idle to only be a couple of degrees above room temp (judging from past experiences and reports), as I have (from what I can tell) pretty decent airflow, and CPU cooling. The temprature readings are still rather baffling, and I am beginning to doubt I'll ever know the true temprature of this setup without sticking a thermal probe on/near the processor.

Thankyou once again for the replies, they're really helping.

Resident · 8 Jun 2013 at 19:55

Bullet5 said:
I've had a look at offsetting the readings, but in all honesty I've no idea what the true temperature is so I could be resetting it way off.

To tell you the truth, I'd expect the idle to only be a couple of degrees above room temp (judging from past experiences and reports), as I have (from what I can tell) pretty decent airflow, and CPU cooling. The temperature readings are still rather baffling, and I am beginning to doubt I'll ever know the true temperature of this setup without sticking a thermal probe on/near the processor.

Thankyou once again for the replies, they're really helping.

Even on the coolest of days, leaving the room window open and letting the CPU auto throttle (AMD Cool & quiet) during it's idle period I've only ever seen temps within +6-7°c and that's with a low ambient of around 17-18°c.

On average whilst I'm just using the PC for light load stuff like web-browsing it's around 10-12°c above ambient. Right now for instance my ambient is 24.1°c and my CPU monitor is reading 36°c with my SP120s only running at just under 1000rpm.