No you dont.
The PCS level isnt neccesarily the root of this, if you have enough memeory in your 406v2 the pcs level is not relevant.
Connect to the system using monitor and when you get the lines of info that tell you what cards are in the system etc you will see freemem=
If your memory is around 55-60meg you have a 64 meg system and that is fine.
If you have more like 20-30 meg you dont and that needs upgrading.
There is also a bug at play here in that when you connect with monitor to a 2.1 27 system (the version that all systems are shipped with) it will report the freemem incorrectly. You need to upgrade to 2.1 35 to rectify this error so that it will report the mem incorrectly. If you try and upgrade a new pcs10 406 while it is on 2.1 27 it will reject it based on the pcs level, in actuality it is this bug that makes it do this and once you upgrade to somethi ng above 2.1 27 you should be able to upgrade without any further complications.
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