运行时间居然不一样 一个机器上的硬盘

[abbott]

一台机器上，有两个硬盘，

可是问题来了，
Hard Disk Sentinel for LINUX console 0.02 (c) 2008 info@hdsentinel.com
Start with -r [reportfile] to save data to report, -h for help

Examining hard disk configuration ...

HDD Device 0: /dev/sda
HDD Model ID : Hitachi HDP725016GLA380
HDD Serial No: GEK854RH19DH6G
HDD Revision : GMBOA5BA
HDD Size : 152588 MB
Interface : S-ATA II
Temperature : 37 °C
Health : 100 %
Performance : 100 %
Power on time: 3 days, 22 hours, 47 minutes
Est. lifetime: more than 1000 days

HDD Device 1: /dev/sdb
HDD Model ID : Hitachi HDT721064SLA360
HDD Serial No: STFD03MG0VKJ0W
HDD Revision : ST0KA36A
HDD Size : 610480 MB
Interface : S-ATA II
Temperature : 43 °C
Health : 100 %
Performance : 100 %
Power on time: 2 days, 3 hours, 14 minutes
Est. lifetime: more than 1000 days


居然开机运行时间不同！

想再挂一个磁盘都困难，
这个阉割版的Dell optiplex 360 只给了两个SATA接口.....