I would say I have close to a top-of-the-line machine, but it would be a good bit over your limit unless you have some of the parts. You can always cut a few corners to save some money, just don't do it in the wrong place. I would suggest picking up the April issue of MaximumPC, it has an article about the best pc parts for the price, and Anantech has a leader board thread (pined to the top of general hardware) where they give a list of peak proformers and value choices for some components. I built my system from newegg not to long ago, here is a list of my components at todays prices.
Basic over view; Aluminum case w/350 ps, Granite Bay board, 1gb Dual channel DDR, 2 80gb 8mb cache hard drives (raid 0), p4 2.66, ATI 9500pro, Microsoft keyboard and mouse, windows xp, ms office, and 5.1 sound. (I priced the system with the 3.06 and 9700pro)
278.00 - Cooler Master ATC-410-SX1. ,Silver All Aluminum Case.
76.00 - ENERMAX EG365AX-VE (W)FCA. 350W Power supply for AMD K7 & Pentium4
239.00 - Gigabyte GA-8INXP, Intel E7205 chipset Socket 478 P4 ATX motherboard, 8XAGP, SATA+ATA133 RAID, , LAN, 6USB 2.0, Dual BIOS Retail
87.00 - PLEXTOR PX-W4824TA/BPS/ 48x24x48 CD-RW - OEM
39.00 - LITE-ON 16X DVD ROM Drive BLACK- OEM
8.00 - *BLACK* PANASONIC 1.44 MB DENSITY FLOPPY DISK DRIVE
196.00 - (2) WESTERN DIGITAL "SPECIAL EDITION" 80GB 7200RPM EIDE HARD DRIVE MODEL # WD800JB
280.00 - (2) GeIL DDR RAM 512MB PC-3200 400Hz Ultra- CAS 2
29.00 - Microsoft Intelli-Mouse Explorer Version 3.0a
26.00 - Microsoft Office Keyboard - OEM
143.00 - Microsoft Windows XP Professional with Service Pack 1 - OEM Full Version
179.00 - Microsoft Office XP Professional - 98/WME/NT/W2K - Academic Version - RETAIL
815.00 - Samsung 191T Silver 19" TFT LCD monitor
548.00 - Intel Pentium 4 / 3.06GHz 512k 478 Pin Processor HT Technology 533 MHz FSB Retail
355.00 - Sapphire ATI RADEON 9700 ATLANTIS PRO ULTIMATE 128MB DDR 8X AGP RETAIL
305.00 - Logitech Z-680 5.1 Metallic Silver Speaker 500Watt THX Certified with Dolby Digital - RETAIL
68.00 - Shipping Fedex saver
Total - $3675.00
This is my system minus the 3.06 p4, 9700pro, and monitor. I have a 2.66 ($230) and the 9500pro ($205) and dual sony 19" (but I doubt the dorm has room for dual 19s

-If you switch the CPU and the video card you can save $468.00.
-You can also buy a cheaper or smaller monitor but I assume you are a gamer (because of insisting on a 9700pro) you will want the samsung.
-If you have an operating system and office you will sabe some money there.
-You may also have some speakers, or maynot be able to have a 5.1 system in the dorm.
-You can save some money on the case and power supply by getting one of the Antec cases and ps combos (130.00)