Overclocking i5 2500k

[Mortex9]

What is the upper limit for core temperatures when stress testing CPU? I am overclocking for the first time. I currently have it stable at 4.9GHz. My idle core temps are 35,35,35,35C. The max core temps I reached while stress testing with Cinebench 20R, 3D Mark Time Spy, and Blender BMW were 74,78,79,75C. I am really looking for what the max temp is and where I should aim for for a safety margin. On other boards I have seen temp range from 72-98C. System listed below.

i5 2500K (Sandy Bridge)

Asus P8Z68-v

Corsair closed loop liquid cooling....I don't remember which one.

[n_scott_pearson]

The typical Tcontrol temperature for processors like yours is typically in the mid-80's. By definition, all cooling fans, blowers, pumps, etc. are supposed to be running at full speed if the temperature of the processor is at or above the Tcontrol threshold, in an attempt to bring temperatures back below this threshold. There are various programs (RWEverything, for example) that can display the contents of MSR 0x01A2, the IA32 Temperature Target MSR, which provides the Tjmax (maximum junction temperature/TCC assertion point) and Tcontrol temperature thresholds for the current processor.

Bottom line, based upon the temperature values you have provided, I would think that you are doing just fine - though you may want to find out what your processor's Tcontrol temperature threshold is so you have something to compare readings to (as well as program the fan speed control capability of your motherboard).

Hope this helps,

...S

[Mortex9]

The software I am using to monitor my temps is Core Temp 1.16. It lists my TjMax at 98C. I do not see a Tcontrol Temp anywhere.

[n_scott_pearson]

Download and install the RWEverything tool. Start it and click on the MSR icon. Then, in the window displayed, click on the User icon to open the User Configuration window. Enter this definition via the Add window box:

IA32_TEMP_TARG=0x1a2

Clicking on Done will close the User Configuration window and open the User Display window. In the value for the IA32_TEMP_TARG MSR, Tjmax is found in bits 16::23 and the Tcontrol Offset is found in bits 8::15. The Tcontrol Offset value, as an absolute temperature, is determined by subtracting the Tcontrol Offset value from the Tjmax value. On my 4th gen Core i7, Tjmax is 0x64 (100c) and Tcontrol Offset is 0x14 (20c), meaning that Tcontrol is 100c - 20c = 80c.

Hope this helps,

...S

[Mortex9]

Now I am really confused. I have been running at 4.9GHz for a few days now. My individual core temps have not gone above 71C and my system seems stable.  I followed your instructions and got the following results; bits 8-15 are 12, bits 16-31 are 62. 62-12=50. Is 50C my max temp? Am I damaging my chip by running at 60-70C?

[n_scott_pearson]

Those numbers are in hexadecimal! Tjmax is 0x62 which is 98. Tcontrol Offset is 0x12 which is 18. Your Tcontrol is thus 80.

...S