Your letting your sound down, a 7.1 soundcard with 5.1 speakers? Creative do now have 7.1 speakers.
Their is now a 5950Ultra. Not sure if it is water cooled.
You RAM speed is one of the lowest, 2100, newer and faster 3200 (400Mhz). Some memory is now @ 500Mhz. This is DDR memory; ever considered faster RDRAM?
250GB SATA150 - What about faster scsi hard drives? Go for two hard drives, maybe an External USB one?