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I have a Windows 8 RTM Enterprise with VMWare 9 installed. I run a couple of VM's but as you can see in the image below my CPU usage never crosses ~50% with 4 VMs running. Even if I run like 8 VMs with a test process to consume a lot of CPU it still remains at 50% but now the host and guest machines slows down. Also, Why does the frequency not change here to the top speed?

The left side of the image contains Process Explorer which shows ~100% Utilization while running 4 VMs. I am not sure, is this is a bug in Task Manager? or is it a setting of mine?


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I strongly suspect your CPU is overheating. – David Schwartz Dec 4 '12 at 21:34
I can see some flames with SpeedFan. Screenshot: I am not even sure what I should interpret from this though. – Omair . Dec 4 '12 at 21:43
After a bit of reading on CPU temps, I think I just burnt my CPU somehow. :( But things make more sense now. Thanks! – Omair . Dec 4 '12 at 22:17
Your CPU is fine, it's just throttling because it's too hot. Either your heat sink fan isn't spinning or your heat sink was mounted improperly, – David Schwartz Dec 4 '12 at 22:19
Ah, great to hear that! Also I cannot select your answer as the correct answer, but thanks again! – Omair . Dec 4 '12 at 22:26

running Prime95 on your host will tell you pretty quickly whether this reading is reality or illusion. it will spike every core (and hyperthead if you have them) to 100% until you kill it, so if you are still reading 50%, then something is wrong with your monitoring.

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@Omair, but be sure to watch your temps during that - if you approach your thermal limit it would be smart to shut that boy down. SpeedFan will provide a fairly good monitor of that. – nerdwaller Dec 4 '12 at 21:26
I did the testing but it's still at 50% and the frequency doesn't increase. The thing is, my PC is pretty responsive while running that. So, I am assuming some setting is throttling the speed. The image link for p95 – Omair . Dec 4 '12 at 21:31
Besides, the Process Explorer graph clearly shows high CPU usage, so running Prime95 won’t make a difference. It is Task Manager that is the problem. – Synetech Dec 4 '12 at 21:32
@Synetech: Task manager accurately takes frequency scaling and throttling into account. Process Explorer shows the percentage of currently-available CPU power. His issue is that only half his CPU power is currently available due to heat. – David Schwartz Dec 4 '12 at 22:32
I get this same problem on my dual core machine a lot. It seems to clunk up and then get hot and sit at 50% for about 10 or 15 minutes and then finally it will wind back down and fluctuate at around 25%. Seems to me that for some reason one of my cores just isn't being used and the other is pegged. – Cory Gross May 17 '13 at 0:14

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