160Gb WD Caviar Blue WD1600AAJS SATA-II 7200rpm 8Mb — 1160.12 RUB
250Gb WD Caviar Blue WD2500AAJS SATA-II 7200rpm 8Mb — 1163.24 RUB
320Gb WD Caviar Blue WD3200AAJS SATA-II 7200rpm 8Mb — 1213.28 RUB
I think you're not from that side approach to the issue.
In an extreme case, pererezat your drive into two (three, n) disks, but still that logical drives that the containers — the brakes have still to be since you will be storing both data and system on the same physical disk. The maximum that you will achieve — the lack of fragmentation of the primary partition, which of course is good, but not very helpful to you.