PA8500 and PA8600 both in the same N4000

[Larry Basford]

We have system with both types of processors installed. Running for years with no problems. We have recently had some lockup conditions and engineers ae pointing at the diff in processors types. Can anyone confirm yea or ney on this mix.
Module Revision
------ --------
System Board A4420
PA 8500 CPU Module 2.4
PA 8600 CPU Module 3.0
PA 8500 CPU Module 2.4
PA 8500 CPU Module 2.4
PA 8500 CPU Module 2.4
PA 8600 CPU Module 3.0

[Luk Vandenbussche]

Larry,
this mix is officialy NOT supported

[Larry Basford]

Thanks Luk,

Do you know of an official HP document I can refrence. I've seen that the PA8500 2.4 and 3.0 together is OK but would prefer them all the same.

[Joshua Scott]

Luk,

Strange that you should say that it is not supported. I've seen this kind of mix before, and it was due to an HP engineer replacing a 440MHz CPU with a 550MHz during a break/fix situation. Also, there was an HP service note that instructed engineers to replace failed 750MHz CPUs on the rp7410 with 875MHz CPUs, and let the board downgrade the speed based on the dipswitches.

Larry,
I have had this type of mix before, and currently, without any problems, but I can certainly see how it could cause a problem. Who installed the CPUs that way?

Josh

[Larry Basford]

Some were purchased used this way and some upgraded with cpu's.

This particular server I have found out also has PDC firmware 41.46 running HPUX 11.0

I'm pretty sure we added the two 8600's last year.
Someware I read that it was no problem to mix them and that the fast CPU will just run slower. It's speed is based onthe bus speed of the system board. But I can't find the documentation to back that up.

[Andrew Rutter]

larry,

I too have seen this mix before and used/installed both pa8500/8600 proc together. This is as long as they are the same speed and part number.

I was told a few years ago that Hp basically ran out of the PA8500 proc so used the PA8600 chips and downgraded the proc speed.

Dont how much truth is in that but could be right?

I bet if you physically look at the cpu's you will see they have the same part number on them.

This is also where the C rev comes in as reported as 2.4 or 3.0 aswell

Andy