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Mismatched P4 Xeon steppings

Cat

Golden Member
I have a box at work that's running two 2.8 GHz Xeons on a 533 Mhz bus. One CPU has a revision of C1, and the other is M0. These are steppings 7 and 5, respectively.

This system will sometimes reboot overnight (when this does happen, it's usually around midnight), and there's nothing in the Event Log that hints at why. It's hooked up to an UPS.

The only oddity I could find in the event log was:

"The CPUs in this multiprocessor system are not all the same revision level. To use all processors the operating system restricts itself to the features of the least capable processor in the system. Should problems occur with this system, contact the CPU manufacturer to see if this mix of processors is supported."

A quick Google indicates this shouldn't be a problem, but I'd like some reassurance. 🙂

Thanks!
 
Run CPU-Z and see if the 2 processors are the same.

It sounds like one is Northwood based and one is Prescott based.
 
Its always best to use the same stepping with cpu's when paired. (Especially servers)
The fact the machine is rebooting for no apparent reason shows its not stable, (though if its always around the same time each night then you might want to look for other problems with the system)
Some systems wont even boot if the cpu's aren't the same, and I'm sorry but I can't reassure you its all going to be fine.
So if this machine needs to be on 24/7 i'd suggest trying to get another matching cpu the same as the latest stepping that you have.
 
LTC8K6, I ran CPU-Z to get the stepping and revision information that was included in the first post.

This is a workstation, not a server.

The machine doesn't need to be on 24/7, and it's never mysteriously rebooted in the year that I've been using it. It only happens at night, while idle. Sometimes I RDP into it from home, so that could be an issue. I've been running Maya, Rhino, and Visual Studio with absolutely no problems. Rendering hasn't crashed, compiles have been flawless, and even my own programming hasn't caused the system to hang often. The only time it does hang is when I'm using fairly new OpenGL extensions which haven't been thoroughly tested by ATi and NVidia.

I'll have to ask my boss if I can get a new CPU, but I have no idea how to buy a certain old stepping of Xeon.
 
Is one a Prescott and one a Northwood? They have different amounts of cache and slightly different instruction sets.
 
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