overclock cpu to 4.5 ghz I ran stress test. but it shows 5.94 ghz in the task manager
albertsstone,
Which "stress" test ?
Microsoft needs to seriously upgrade Task Manager, as the "Performance" tab leaves much to be desired. Compared to utilities such as CPU-Z, Task Manager is often inaccurate concerning parameters such as CPU frequency, so what you're seeing is not at all unusual. Additionally, Task Manager's "CPU % Utilization" is
highly misleading.
“Stress” tests vary widely, so it's important to be very specific concerning what utility and test(s) you ran. Most "stress" tests are fluctuating workloads, as are apps and games. You can't depend on Task Manager to be anywhere near accurate, since it won't tell you if your CPU is in an
overloaded or
underloaded "workload" condition.
Here’s a comparison of "stress" test utilities grouped as
thermal and
stability tests according to % of TDP, averaged across six processor Generations at stock settings rounded to the nearest 5%:
Although these tests range from
70% to 130% TDP workload, it's very interesting to observe that
Windows Task Manager interprets every test as
100% CPU Utilization, which is
processor resource activity,
NOT actual workload.
As you can see from the scale, Task Manager's major shortcomings are that it only scales to 100% "Utilization" and that it doesn't scale in actual "workload". It's clear from Intel's Datasheets that a CPU is at
100% workload only when it's at
100% TDP (Thermal Design Power), which is the
only instance when Task Manager is accurate.
To be clear, when actual Power consumption (Watts) = your CPU's rated TDP, then you're at 100% TDP workload. Keep in mind that unless overclocking or running a heavy AVX workload such as Prime95 with AVX, only
flagship CPU's such as the i7-3770K can reach their rated TDP at stock settings. Although your i5-3570K shares the same 77 Watt TDP rating, it consumes less power as it lacks Hyper-Threading, has a lower Clock Speed and less Cache.
Since Task Manager doesn't indicate true workload, which is %TDP, it's only a
very "general" indication of what your CPU is actually doing. For example, when running a "stress" test utility, if you use a simple, straight foreword utility such as
Core Temp to observe the actual measured Power (Watts) your i5-3570K is consuming compared to Task Manager's "Utilization", the disparities become clear.
So if you select an "
overload" utility from the above scale that will cause your overclocked 77 Watt CPU to exceed its rated TDP by, let's say, 125%, which for your 3570K would be 96.25 Watts, Task Manager will still only show "100% Utilization". It's obvious that Task Manager needs some work.
CT