Server crashing interfaces NIC

Hi,

I have an HP Proliant server x86_64 RoS was running 5.2 but already upgraded to 5.9, 5.11 and finally 5.12 (stable at moment).
What happens is that nothing to the network interface to communicate with the host behind it. suspicious network card swapped for another quad ethernet msi support, Intel 82576, and the problem occurred.
Finally as said updated to version 5.12, and so far this has not happened more on that server.
Anyone ever had a problem like this, because another issue I’m also taking another server, it’s no lock out, what I realized is that the muli-cpu option is enabled, but found nothing talking about this option in versions 5.x.
The other server is a dual core with 2 gb ram 2.9gh.
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