Well Im sure u guys know I got server

but I stuck with lil question what should I do.
PUT it on it's own hdd: bit slower, it's IDE but there's nothing on it, nothing
Maxtor DiamondMax Plus 45 Hard Drive
Model: 51536H2
Formatted Capacity: 15.3GB
Interface: IDE
Ultra ATA/100 Data Transfer Rate
2 MB SDRAM Cache Buffer
<8.7 ms Seek Time
Rotatioal Speed: 7200RPM
Average Latency: 4.17 ms
or
Move it to the same hdd as my os: RLY fast but has Vista on it
WD Black caviar 640 GB SATA
Maximum external transfer rate 300MB/s
Sustained data rate 145MB/s
Average read seek time 4.2ms
Spindle speed 7,200 RPMB
Cache size 32MB