I am running Centos 7 in Virtualbox 4.3.14. The VM is configured with

  • 2 CPUs
  • 4 GB RAM
  • 3.10.0-123.4.4.el7.x86_64 kernel

The host machine is running

  • Windows 7 Pro SP1 64-bit
  • Intel i7-4790 CPU, Hyper-Threading enabled
  • 16 GB RAM

Yet, when I start up this VM, it bring my entire system almost to a halt, including my host OS. In Process Explorer of System Internal, I can see all my cores are maxed out by VirtualBox. On my VM using top, the load average is about 2 when the system "idles".

Previously I used to run a similar configuration using only a laptop with 6 GB of RAM without any problems.

What else can I try to make this VM usable?

  • Could you show what you see when you run top on your guest?
    – Marcelo
    Aug 5, 2014 at 14:52
  • I cannot. I need more "rep".On the i7 server get a load average of 15.37 (top processes are java processes that take 12.5% - 40.6% each). I copied the same VM to an i5 laptop with only 8 GB RAM and got a load average of 2.28 (top processes are the same java processes that take 17.3% - 17.6% each). Aug 5, 2014 at 15:57

1 Answer 1


Turns out the physical host machine's CPU fan was never plugged in and because the CPU was overheating, the system slowed down to protect itself.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.