(1) If the temps are at idle, I would recommend running prime 95 and monitor temps. Load temps are much more important than idle temps. Prime 95 will put a even load on each core so if you still have a 6 C delta on your cores (Looking at Max values), then it might be sligthly eneven thermo paste application or slight diff in pressure of the HS core
(2) your +3.3 looks a little low 3.3 +/- 5% = 3.14->3.46 V. +5/+12 look good.
Core 1 lower than others by 7 C from others - Not really a biggy. I assume prime 95 did not give any errors, How long did you leave it run? For just to check temps - 15 mins OK, but for stability I'd run a min of 2 hours.
Your over all temps are a little on the high side since you are not over clocking your proccessor (I do not like to go above 60 C although my CPU suppose to be good to 72 C -I5-750 OCed). Intel HSF's are normally adequate, although lousy. Myself I do not even install them. Just buy a after market and install. Normally look for one with a backing plate as I also hate the push-pins.
@RetiredChief I ran prime95 for 10 mins I think, i was watching the tempratures getting high until they stopped at 65C .. Is this means that core 1 isn't performing well?
What should I do to low the temperatures? It's 31 C in the room and it's a good temperature ,sometimes it reaches 41 C. When the air condioner is on the temperatures are 5 C less..
Do I have to buy an extra fan?
And what is the max temperature for the CPU , (GPU max = 105 C )
Is the fan speed normal? what is the default speed of the HSF?
(1) The Max temp for the Q8300 is 71 C, and I believe that at 80 C the CPU will throtle back to protect the CPU.
(2) The most likely cause for lower temp on CPU1 is better thermo contact between the CPU and the HSF. You could remove the HSF, remove the thermal paste (use alcohol, preferably 91%) and reapply - Use artic silver 5, and just a small amount (about the size of a grain of rice) and spread thinly.
(3) Your ambient room temp is high and will cause higher than normal core temps. Normal room temps is around 22 -> 25 C.
(4). It appears that you cpu fan is at max. What other fans do you have. At a min you should have one at the back, blowing out, and one in the front blowing in. To check if your case has good air flow remove the side cover - Good case airflow you will only see a few degress drop. You could also get a better (higher air flow) fan for the rear.
I would add a fan at the back of the case blowing out, And either (1) replace the HSF - best is one with a backing plate,or (2) at least remove HSF, put new thermo paste and re-install. 68 C is high for a non overcloced Q8300 with ambient temp of 25 C - I would expect closer to high 50's.
recently i bought a q8300, for dirt cheap in which idle temp is 55 and after 3 runs of intel burn test i.e on full load is 95+degree, em running on slock cooler,
my question is, my cooler is running is 3500rpm all the time, from 0-100% load, and it has only 3pin fan connector(but intel logo on it), is it a fake one?? plz help out