Today, I started configuring server IBM System x3650, with 6 drives 750GB.
I boot up from ServeRAID support CD to configure the array in RAID 5, and noticed that I can make only 2TB logical drive instead of 3,5TB expected (6x700GB-1x700GB for parity).
I download fresh firmwares (and addicionaly noticed that IBM SAS Drives has a critical update. And there was no difference. I noticed that ServeRAID Support CD use kernel 2.4, and try not to configure array from support cd.
By entering controller BIOS (CTRL+A), you can easly configure array how big you want :). I send an information to IBM support, they replied that in next verison of support CD kernel 2.6 will be used.