Win XP Pro slower after adding hard disk

Here’s my system:
Windows XP Professional SP1 with all updates
Pentium III 750MHz Slot 1 SECC2 CPU
640MB RAM
Abit BX6r2 (440BX) motherboard
Hercules TNT2 Ultra Video Card
Linksys NIC (10/100 autosensing PCI)
Creative Labs Sound Blaster 16 PnP(ISA)
40GB Western Digital Hard Drive (boot)
Lite-On 16x10x40 CDRW
Added 80GB Maxtor Hard Drive

Configuration:
Pri. Master: 40Gb boot
Pri. Slave: 80GB
Sec. Master:
Sec. Slave: LiteOn CDRW

After adding the 80GB hard drive the system seems slower to respond. Sometimes programs take up to 10 seconds (or more) to launch. This problem did not occur prior to adding the 80GB drive.

Anyone have any ideas that will allow for the system to return to its normal speed (other than removing the 80GB drive)?