I didn’t do the core parking thing as I already had the BIOS set so that the CPU power saving and throttling features were all disabled.
What happened is that I noticed that one of the CPU cores was spiking at low buffer settings - but only when I was recording. This led me to suspect the problem was caused (or at least exacerbated) when writing data to the hard drive. I changed some of the hard drive cache flushing settings in device manager and things improved dramatically. After a bit more research I determined that I should have installed Win 7 using AHCI instead of ATA mode for the hard disk controller. With Win XP it was stated that ATA is the proper way to go as AHCI could cause data loss/corruption and just used this by default when I set the BIOS up for the new i7 computer with Win 7. Luckily, I was able to find a method via Google search that allowed me to change to AHCI without reinstalling Windows. I would not use ACHI with Win XP, but you may want to experiment with your cache settings and I advise that you use the BIOS settings that will keep your CPU with all cores active and running at rating speed constantly. I believe that these things may help with the CPU overload on export problem as well.
As I mentioned in a related thread, there appears to be an issue with resource contention in Nuendo/Cubase. There is no reason we should see the CPU spiking on very powerful computers with projects that are not that CPU intensive. I’m pretty sure that the GUI/graphics can often spike the CPU and cause problems when it should not - I have had (and continue to have) problems with that. I also use C6 and it becomes extremely sluggish when I have many events chopped up and in view - this sluggishness goes away when I hide the tracks in folders. I went from C4 to C6, but evidently this was a problem with C5.5 which I believe was resolved with an update - unfortunately it came back with C6 and is still there in the recent C6.0.1 update. This is a real shame as C6 has some absolutely killer new features. I just hope that this sluggishness does not make it into the N5.5 update as it did with C6. Also, just bringing up the Tuner plug-in at low latency will spike the CPU (I believe this to be graphics related as I was unable to use the Peterson Strobosoft for this reason as well).
I really wish that SB would start making these issues a priority. Sadly, it would appear the most of the users are either using high buffer settings and relying on direct monitoring (which should NOT be necessary in most cases with today’s powerful computers) or are just running smaller less CPU intensive projects. I’m amazed that I rarely see anyone complaining about the GUI sluggishness in C6 and CPU spiking in general. Evidently I’m pushing my system more than most do, but my competition typically use PT HD and I should be able to run low latency sessions as well as they can (or better!) without having to deal with CPU spiking when my ASIO meter is only registering 10-15%.