Go here, click Customize It under the system to the furthest left which is $459.
I wouldn't recommend that route as currently that gets you the system with the 2.0 GHZ cpu, rather than the 2.4/533.
You can definitely get this system down cheaper, but, if you go below $749 you miss out on the $50 coupon. I've been recommending to people to do the deal as follows:
Dell Dimension 4550 Series Pentium® 4 Processor at 2.40GHz with 533MHz system bus/ 512K L2 Price: $759.00 ( - $150)
Dell Dimension 4550 Series: Pentium® 4 Processor at 2.40GHz with 533MHz system bus/ 512K L2 Cache DA4524 [221-0996]
Memory: 256MB DDR SDRAM at 333MHz 256M3 [311-2075]
Keyboard: Dell® Quietkey® Keyboard QK [310-1582]
Monitors: FREE UPGRADE! 15 in (15.0 in viewable) E151FP Flat Panel Display E151FPP [461-7994]
Video Cards: New 64MB DDR NVIDIA GeForce4? MX Graphics Card with TV-Out 64NV420 [320-0476]
Hard Drive: 30GB Ultra ATA/100 7200RPM Hard Drive 30 [340-7396]
Floppy Drive: 3.5 in Floppy Drive 3 [340-1927]
Operating System: Microsoft® Windows® XP Home Edition WHXP [313-7222] [412-0306] [420-3079]
Mouse: Dell® 2-button scroll mouse SM [310-1871]
Network Interface: Integrated Intel® PRO 10/100 Ethernet IN [430-0412]
Modem: No Modem Requested N [313-3607]
CD or DVD Drive: FREE UPGRADE! 40x/10x/40x Max CD-RW Drive with Roxios Easy CD Creator® 40CDRWP [461-8074]
Sound Card: Integrated Audio IS [313-0847]
Speakers: No Speaker Option N [313-4514]
Software Bundles: Microsoft® Works Suite 2002 w/Money Standard WORKS [412-0133]
Virus Protection: Norton AntiVirus? 2002, 90-day introductory offer NAV2002 [412-0259]
Digital Music: Dell Jukebox powered by MusicMatch MMBASE [412-0298]
Limited Warranty, Services and Support Options: 1 Year Limited Warranty plus 1 Year On-site Service B111YOS [950-1230] Internet Access Service: 6 Months AOL,Featuring the Netbusiness Service for Small Business AOLSMB [412-0280] [412-0287]
Giving 256MB ram instead of only 128, but only a 30 gig drive instead of 60, ending up with a $10 higher total ($609 vs $599) but I think the RAM is more important. You can easily get the system for $589 but it is worth $20 or $30 more to get the upgraded video, etc, making it eligible for the $50 savings.