Can a bios update alter temp readings?

My new Asus P5Q Deluxe mobo - v0605 BIOS read the CPU temp fine -- but when upgrading to BIOS 1406, the CPU temps stated are wrong -- the main temp is stuck between 18 and 20C (the mobo being 39C). Cores 1-3 all read 38C and core 4 reads 41C.

The main CPU temp will go between 18 and 21C, but the 4 core temps don't waver.

I applied the new BIOS using the crtl-F2 method accessible during POST.

I didn't do a 'load default values' -- is that necessary, and might that be the problem?

If not, might re-flashing solve the problem?

Or are others having this problem too?

My CPU is a Q9550 (E0)

Thx!

Yes a bios update can alter temps and other things as well. It will probably be fixed in the next bios. That is of course if you are using the asus probe tools.

It should not change a reading from coretemp, realtemp.

1) a bios change can change CPU temp.
2) temp is stuck, you mean it doesn't change at all? Even under load?
3) a spread of 4C between cores isn't that unusual.

What are you using to read the core temps?

deeppow said:

1) a bios change can change CPU temp.
2) temp is stuck, you mean it doesn't change at all? Even under load?
3) a spread of 4C between cores isn't that unusual.

What are you using to read the core temps?

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I'm reading the BIOS value for the CPU - and also for the CPU plus all 4 cores I've used Everest Ultimate and CoreTemp.

I've updated BIOSes on boards before; this is the first time I've encountered this.

Maybe it is a bug on Asus' part... but before the upgrade, the CPU temp was shown at a value I could believe. (With the room temp at 24C, there is no way the CPU can be 18C while also reporting the four cores are 38/38/38/41 (which it still is doing)

Gunlance said:

Yes a bios update can alter temps and other things as well. It will probably be fixed in the next bios. That is of course if you are using the asus probe tools.

It should not change a reading from coretemp, realtemp.

Click to expand...

Not using Asus probe - both the BIOS display and via Everest (Coretemp too).

Now I have seen valid fluctuations in the core temps, but why would the main CPU temp be so much lower? I know this value is kinda BS by comparison, but I've never seen it as being 20 degrees cooler. (maybe the tuniq tower 120 is that good at moving heat away from the surface of the CPU?)

I am inclined to believe the core values; weird how in idle it's always 38/38/38/41, but as I increase load the values slowly rise.

I'll still do a cmos reset...

Your temps seem perfectly normal to me. What were they before you updated the BIOS? A CPU case temp below the motherboard temp is normal on new high-end boards. Everest tells me motherboard temp is 48C, north/south bridge are both ~58C, and CPU temp is 28C. CPU cores, however, are all around 55-58C.

I'm not sure if it's all chips, but it happened with my Q6700 and Q9550 after I went from BIOS 0704 to 0803 it started reading a very low CPU Temp. All the cores read normally, but the actual CPU temp is off for some reason, and is still off even with the 1406 BIOS. Not a big deal since you can pretty much gather from your core temps (if they're all 3-5C in difference) what your CPU temp is

Thermodynamic said:

.....

I've updated BIOSes on boards before; this is the first time I've encountered this.

Maybe it is a bug on Asus' part... but before the upgrade, the CPU temp was shown at a value I could believe. (With the room temp at 24C, there is no way the CPU can be 18C while also reporting the four cores are 38/38/38/41 (which it still is doing)

Click to expand...

Well no way you screwed up the update. If you did you would have bigger problems like no boot.

The CPU temp will be different than the core temps. The cores each read from a sensor within that particular core while the CPU temp is read from a sensor placed between the 4 cores. But I agree that the CPU temp is amiss with it being lower that the air temp when you're air cooling.

And yes I would say it is an ASUS problem, I tend to disregard the CPU temp and use my core temps anyway.

By the way, nice handle!

petteyg359 said:

Your temps seem perfectly normal to me. What were they before you updated the BIOS? A CPU case temp below the motherboard temp is normal on new high-end boards. Everest tells me motherboard temp is 48C, north/south bridge are both ~58C, and CPU temp is 28C. CPU cores, however, are all around 55-58C.

Click to expand...

The P5Q Deluxe was new; before upgrading the BIOS, I made reference to only the BIOS monitor -- which had the CPU at 30C -- the mobo at 32C. Since the upgrade, the Mobo is still ~32 but the CPU is 20.

And I still have yet to see the cor etemps go up from their levels, even under some load. I'll have to continue working and to clear the CMOS as well - I had forgotten to do that...

deeppow said:

Well no way you screwed up the update. If you did you would have bigger problems like no boot.

The CPU temp will be different than the core temps. The cores each read from a sensor within that particular core while the CPU temp is read from a sensor placed between the 4 cores. But I agree that the CPU temp is amiss with it being lower that the air temp when you're air cooling.

And yes I would say it is an ASUS problem, I tend to disregard the CPU temp and use my core temps anyway.

By the way, nice handle!

Click to expand...

Thanks!

I have now tried Coretemp 2.70 -- core temps are 38/38/38/41. (Core 0-3 respectively). When testing the sensors, it is core 0 that has a sensor variation between 2 and 4 (multiple tests), and cores 1-3 having 0 movement suggesting those 3 cores won't give an accurate response.

I'm going to agree; this is an Asus problem -- the CPU itself can't be bad.

Maybe I'll re-flash the BIOS.

Oh, running Prime95, the main CPU reading did go up to 23 and cores 0 and 1 went up a bit too - cores 3 and 4 did not change temps, and Coretemp showed 100% load on all 4 cores.

---UPDATE---

Clearing the RTC and re-flashing the same version had no effect.

I've done some research on the web. Nothing 100% conclusive, but there's a lot to make reasonable inferences from:

1. Some other people have reported sensor reading problems too.
2. Someone with a Yorkfield E0 went from 1106 to a previous version because of massive instability.
3. v1406 fixes some issues with C1 spec chips - nothing said about E0
4. E0 is a newer Q9550 release, so maybe I'm just unlucky right now and need to wait for the next version
5. As what I've added up re: sensor issues is inconsistent, unless the various apps are reading cores 0-1-2-3 as 3-2-1-0, the problem is indeed the mobo. But I've used these same apps on my previous mobo and without incident.

Still, especially with a 3 year warranty, for CPU or Mobo, I'm not going to fret just yet.


I do have another P5Q Deluxe on order; I might swap the board out but right now my instinct is saying there will be a BIOS fix that'll be out later this year.