I am having problems with my PC and am pretty sure the Mobo is to blame. Please can you confirm that the problem is what I think it is before I send it off for a refund/replacement. - Thanks
For Ease of reading I have broken this down into a brief list and then detailed explaination of the problem. Please check the detailed version before asking any questions about what I have done to fault find/rectify the problem as it is likely I have already stated it.
CPU fan displaying erratic results (between 0 rpm and 24500 rpm) - Fan itself only capable of operating between 900-2500 rpm.
Results varified with BIOS and 2 programs.
BIOS flashed, connector disconnected/reconnected.
No visible faults with hardware.
Fan operating correctly, but Monitor(s) not showing this.
Here's the detailed version;
My PC works fine at all times, no crashes, freezes, hangs or weird behaviour, asides from the problem with the fan. The readings that I get from the fan sensor in the BIOS, Speedfan and the ASUS AI Suite all display erratic and (often huge) numbers.
Speedfan and the AI Suite display the same values (no way of comparing directly to the bios, but the trend is the same), currently showing at 19,820 rpm (the fan information says it is capable of running at 900-2500rpm). These numbers will display all the way down to zero (where I get an warning, saying CPU Fan 0rpm - where i promptly panic and rip the side off my case, as the only noise this thing kicks out is from the HDDs).
Looking inside I can see the fan is quite happily whirring around and even responds correctly to increased temp from CPU itself (i.e. it speeds up).
I have checked all the cabling for the fan, to make sure there are no frays or shorts, have disconnected and reconnected the 4 pin to 4 pin connector and have updated the BIOS. None of these things seem to have made bugger all difference.
It is worth noting that this it is completely random as to when this happens (since I doublechecked the BIOS the speed is happily within parameters, but is not likely to be so after next reboot, or even the one after that).
Components of importance (feel free to ask for others if you think it'll help)
Arctic Cooling Freezer Pro 7
i5 2500k (OC to 4.2) - NOTE - I have removed the OC to see if this is the case, but still get the same message, so it stays at 4.2.
Asus P8Z68 -V LX mobo
Go into the bios and find the smartfan settings and calibrate your fan. Some boards will even calibrate 3 pin fans; mine works with either 3 or 4 pin designs. Then set the smartfan to manual or quiet mode after calibrating. Some fan speed variance is normal; mine revs up everytime I turn the system on, but once smartfan loads the settings, it quiets down after three seconds. If you still don't like the noise, use this: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
I don't mind the criticism; I answer alot of posts so if I missed something, my apologies. Will study your post again. The bios won't automatically control your fan speed except on a few oem boards. And any hardware monitor software is subject to bad readings. They can't work perfectly with all boards.
before returning the motherboard, you might try another fan on your CPU to make sure that where the reading errors or coming from, or if you hae another MB, try your fan on it to see if you get the same results. Either way you would be confirming where the error is before sending back a motherboard. Just be sure to get the new one from a store that you can return it to such as fry's. I think they have the coolermaster hyper 212 plus for about $25.00 right now so you won't be out much either way. plus that is a great aftermarket cooler anyway.
The bios won't automatically control your fan speed except on a few oem boards. And any hardware monitor software is subject to bad readings
Thankfully the BIOS doesnt control the speeds, as the BIOS monitor displays the same as the AI Suite (the software tool that came with the mobo, so if this does not display the correct values, I doubt anything else will)
try another fan on your CPU to make sure that where the reading errors or coming from
Although I hate doing this, I unboxed the ol' Intel fan (the one that everyone loves to hate, that comes with Intel CPUs) plugged it in, and.... same thing. obscene values being returned from the CPU speed. - Says Mobo to me.
use this to test if the fan speed is reading the right one http://www.hwinfo.com/ and with cpud did you use the cpuid hwmonitor
I have used 3 fan speed monitors, not to sound condecending, but if all 3 return erronous results I doubt a forth will fare any better.
I think I'll stick with what o1die said, "They can't work perfectly with all boards" and keep an eye on my mobo for other stange goings on.
Thanks to all for your input,
It helped me clear up the issue, and put my mind at ease regarding the severity of the issue.