Strange behaviour after CPU change

Issues related to hardware problems
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XoCinek
Posts: 2
Joined: 2014/03/21 12:26:02

Strange behaviour after CPU change

Post by XoCinek » 2014/03/21 12:34:57

Greetings.

Maybe someone had such "problem".

There are several servers on Centos 5.X - every updated to nowest, they works PERFECLTY WELL.

Few of them we wanted to upgrade by hardware. So, it was MotherBoard's GIGABYTE with CPUs i7-3820 on socket 2011 (grrrrr).

Works perfectly again and still.

And then starts funny thing. New one, everything the same, one thing changes - CPU - to i7-4820K

Whats happening? Well.

1. We cannotreset machine by reboot or even hard reset - it froze exactly on Waiting for driver initlialization. Forever. It does not happen when we turn power cable out and than plug it in.

2. Sleep functions (every, simple bash sleep, php sleep, nanosleep, sleeps in C++) adds 2 seconds every time, so in eample sleep 2 works for 4 seconds, sleep 10 for 12 seconds, etc, etc, etc.


It does not happen on ANY Centos 6.x even oldest one 6.0

Well, we think it would be rather kernel problem (2.6.18.X on C5 and 2.6.32.X on C6) but reinstaling more than 20 machines is .... out of questions :-)

Someone had something like that? Any suggestions?

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Super Jamie
Posts: 310
Joined: 2014/01/10 23:44:51

Re: Strange behaviour after CPU change

Post by Super Jamie » 2014/03/21 20:37:14

I'm not 100% sure how to match i7 and Xeon cores, however it is possible that your i7-4820K maps to the same core family as the Xeon E5-4600v2, which is not supported by the EL5 kernel:

https://access.redhat.com/site/support/policy/intel

XoCinek
Posts: 2
Joined: 2014/03/21 12:26:02

Re: Strange behaviour after CPU change

Post by XoCinek » 2014/03/25 18:02:30

Hi.

It is not processor problem. Both of them works perfectly on ... lesser revision of mainboard.

After investigation it seems to be a BIOS problem. New mainboards - GIGABYTE GA-X79-UP4 rev 1.1 Dual UEFI Bios - have F4 and F5 BIOS versions. Older ones - rev 1.0 Dual Bios - have F3 BIOS. There are a lot of problems in these new bioses described accross the internet forums AND Gigabyte knows about it - They rather don't care. Worse: new rev 1.1 BIOSes have "secure bit" that disallow to downgrade to F3 BIOS.

Well if someone have rev 1.0 of these boards NEVER EVER upgrade to F4 or F5 BIOS unless You want to play a game called "how to the hell now downgrade my BIOS" :-)

Now, we are waiting for one resolve from our Gigabyte contact. I'll describe it after it is done in .... two, three weeks :-)

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