Is it Power7 or is it Power7+?


Last year I budgeted for 3 P740C model’s to replace 3 P6 550 models that were getting long in the tooth. Because of the long lead time in our budget process and the continued downward pressure from IBM on their pricing, I was able to purchase 4 P7+ 740D models.  That is a big win for us.

After implementing new 7042-CR7 model HMCs (which I recommend everyone upgrade to) and powering on our first box, I noticed that the latest HMC code reports the server has a Power7 and not a Power7+.  The Power7 chip has been out for nearly a year, and the HMC has been through several updates since then, so why does it not show Power7+ the way it did for Power6+?  Here’s what the screen looks like:


So, what does the LPAR say when it’s powered on?  Everywhere I look, it’s Power7.  Here’s what the system thinks the CPU is:

nim # lsattr -El proc0
frequency   4228000000     Processor Speed       False
smt_enabled true           Processor SMT enabled False
smt_threads 4              Processor SMT threads False
state       enable         Processor state       False
type        PowerPC_POWER7 Processor type        False

And prtconf:

nim # prtconf 
System Model: IBM,8205-E6D
Machine Serial Number: 
Processor Type: PowerPC_POWER7
Processor Implementation Mode: POWER 7
Processor Version: PV_7_Compat

I do have a Power7 server running in Power6+ compatibility mode, here’s the output of prtconf on that server:

# prtconf
System Model: IBM,8202-E4B
Machine Serial Number: 10418BP
Processor Type: PowerPC_POWER7
Processor Implementation Mode: POWER 6
Processor Version: PV_6_Compat

So, maybe the OS commands aren’t aware of the CPU compatibility mode.  This is the latest firmware and the latest AIX 7.1 level.  I’m also running the latest HMC code, and I’ve confirmed the same behavior in the latest VIOS level (

Of course, the question was asked, did we really get what we paid for? So, I called my IBM Business Partner and asked their Technical sales team to dig into this.  The box does have Power7+ processors, so it’s wasn’t mis-ordered and it WAS built correctly in the factory. They reached out to some other customers running a new P7+ 770, and they’ve confirmed the same behavior there, so I assume this is the same across the product line.

Then I had a bit of luck. As part of this upgrade, I’m testing AME on our non-production servers.  The amepat tool, shows the correct processor mode:

nim # amepat

Command Invoked                : amepat

Date/Time of invocation        : Fri Sep 27 11:53:38 EDT 2013
Total Monitored time           : NA
Total Samples Collected        : NA

System Configuration:
Partition Name                 : nim
Processor Implementation Mode  : POWER7+ Mode
Number Of Logical CPUs         : 4
Processor Entitled Capacity    : 0.10
Processor Max. Capacity        : 1.00
True Memory                    : 4.00 GB
SMT Threads                    : 4
Shared Processor Mode          : Enabled-Uncapped
Active Memory Sharing          : Disabled
Active Memory Expansion        : Enabled
Target Expanded Memory Size    : 8.00 GB
Target Memory Expansion factor : 2.00

There we see the expected Power7+ mode.  This command works and reports the processor correctly on systems without AME enabled, so it can be used on any LPAR to show the correct processor type for Power7+ systems.  Here is the output on our Power7 LPAR running in Power6+ mode:

# amepat
Command Invoked : amepat
Date/Time of invocation : Wed Oct 2 12:41:43 EDT 2013
Total Monitored time : NA
Total Samples Collected : NA
System Configuration:
Partition Name : tsm1
Processor Implementation Mode : POWER6

So, amepat doesn’t report Power6+ for Power7 systems running in Power6+ mode.

Our IBM client team is looking into this issue, and I expect the relevant commands will be enhanced in a future service pack and HMC level.  But, in the mean time, we can prove that what we ordered is what was delivered.


IBM’s answer:

Historically IBM has not included the “+” on any of our products (ie Power 5+, Power6 or Power7+).  You can open a PMR and request a Design Change Request (DCR) to have the “+” added for Power7 servers.

That is an interesting answer to me.  We never purchased any Power6+ servers, so I can’t comment on what the OS commands, lsattr and the like, may or may not report. But, the HMC most definitely did report a separate compatibility mode for Power6+. My only thought is that the Power7+ CPU didn’t introduce a new operational mode, which is a little surprising to me because of some of the work done in this chip.



    For the purpose of the HMC and LPM there is no difference between POWER7 and POWER7+ thus there is no setting specifically for POWER7+
    at least that is the way I recall it from the last POWER conference – looking for documentation on that.

    Bryon Denne

    It’s hard to find knowledgeable folks during this topic, however, you could be seen as do you know what you are dealing with! Thanks

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