I bought three WD Caviar Black 7200 HDDs. I've put all three in a stripped raid on my 2009 MP. The block size is at 32, only because thats what it defaulted to. Anyway, everything seems to be opening a bit slower than expected so I ran Xbench...below are the results. Results 193.15 System Info Xbench Version 1.3 System Version 10.6.1 (10B504) Physical RAM 3072 MB Model MacPro4,1 Drive Type Mac OSX Disk Test 193.15 Sequential 196.84 Uncached Write 401.05 246.24 MB/sec [4K blocks] Uncached Write 373.99 211.60 MB/sec [256K blocks] Uncached Read 76.15 22.29 MB/sec [4K blocks] Uncached Read 494.63 248.60 MB/sec [256K blocks] Random 189.60 Uncached Write 78.39 8.30 MB/sec [4K blocks] Uncached Write 713.67 228.47 MB/sec [256K blocks] Uncached Read 276.36 1.96 MB/sec [4K blocks] Uncached Read 301.07 55.87 MB/sec [256K blocks] I was expecting much more than this, did I do something wrong? I've used drive bays 1-3 for the raid.