Hi, having just spend 6 hours rebuiling my PC (cutting holes for extra fans, replacing 80mm fans for 92mm fans, cleaning coolers, re-positioning hard disk and cables) i've powered it back up and got a cooler and quieter PC for my troubles however, as usual, my CPU temps are a little odd (to me anyway) its a C2D Q6600 @ 3.2 (1.2625v according to cpuz, although i think its 1.3625 in the BIOS) on an abit ip35 board, with a zalman 9700 cooler. this is the 4th time i have re-installed the cooler, its always been put on with a good thermal paste, but my core to core temps can differ by up to 10 degrees at times. Core 0 & 1 always run hotter than cores 3 & 4. The only thing i can think of is that when i bought the CPU it had been lapped by the previous owner, but would that really make a 5-10 degree difference?? if it is the lapping that isnt flat, whats the best way to check it, and correct it? thanks
I always have this. I found using Realtemp show it as worse as it is, what temp software are you using?
This has nothing to do with the external surface of the CPU. Some CPUs have borked sensors which don't give correct/accurate temp readings (eg I had an i7 970 and two of the six cores were reading 14C apart under load, which is A LOT). Also it's possible that the hotter cores (half the die basically) aren't making good contact with the underside of the heat spreader. Unfortunately there's nothing you can do about that, but it's nothing to worry about either. The Zalman 9700 is a nice cooler btw - I got one for Christmas in 2007 and I was very pleased lol
So long as its nothing to worry about i did wonder if the lapping was slightly wonky, but if its a normal trait i'll live with it. Btw, on question i always ment to ask but darnt(!) Which way should you mount a zalman 9700, i have it so the heat pipes are horizontal, and the fan blowing into the psu (its an old cade so the psu is at the top) that right or should the heatpipes be vertical with the fan blowing to the side?
There's no right or wrong way - whatever works for you is fine. I had mine mounted horizontally with the fan taking air from the front of the case and exhausting out the back.
It could also be a slight thickness in the TIM in that area or a slight fault with those cores that makes them hotter...
How much difference in the temps is there, and what kind of actual temps are you looking at? In a multi-core CPU I've always found not all the cores run at the same temperature, either due to variance in the actual CPU or the mounting of the cooling setup - anything up to 5 C difference between cores (with all at 100% load) is OK in my book. EDIT: Just re-read the original post, are you saying one or two cores can be 10 C hotter than others? That does seem a rather big difference. How does the CPU cooler mount? I'm wondering if there could be less pressure on one side than the other. If it's currently vertical, have you tried laying the case on it's side to see if this makes any difference? If it does that could certainly indicate the mounting being at fault.
