Intel will announce their new chipset revision support 533FSB on March ~28 (according to Abit's release date for these boards). The 2.2GHz and 2.4GHz P4 supporting 533FSB will also be announced at that time. For 2.53Ghz (and 2.66GHz if competitive pressures require), you'll have to wait another three months after that--end of July.
If you are purchasing a prebuilt Intel system (and thus will not overclock on your own), then you should definitely wait until April and buy a 2.2Ghz or 2.4GHz system using Intel's new chipset with 533FSB; waiting until April will also get you the newest 2D/3D graphics technology. If you can hold out until late July, that might be another option to consider, as a faster P4 and even faster video card will be available. A 2.53GHz or 2.66GHz P4 with top-end Geforce4 Ultra or Radeon3 graphics would be one hell of a performer.
A Dell P3-1.0GHz is a reasonably fast system. I personally would want any Intel upgrade to include the latest 3D graphics (top end Geforce4 or Radeon3), a top performance hard drive, 533FSB, and at least 2.4GHz of Intel P4 processing power. A quick run down of retail Dell purchase options...
BUY NOW
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+ get your system now
- fastest system is 2.2GHz
- stuck with a slower 400FSB that won't support future P4 processors
- stuck with Geforce3 or Radeon2 video card that will be obsolete by February 4
- stuck with slower memory (as a result of lower FSB)
BUY APRIL
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- get your system in April
+ fastest system is 2.4GHz; 2.2GHz systems are less expensive
+ get 533FSB that will support future P4 3+GHz processors
+ get faster GeForce4 Ti 4400 video card that will do much better with future games
+ get faster memory (as a result of higher FSB)
+ get faster hard drive (Dell isn't yet using the newest drives, but will be by April)
+ get more affordable DVD-RW recording
BUY END JULY
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-- get your system in August
++ fastest system is at least 2.53GHz; 2.4GHz systems are less expensive
+ get 533FSB that will support future P4 3+GHz processors
+ get an even faster GeForce4 Ti 4600 (=GF4 Ultra) video card that will do much better with future games
+ get faster memory (as a result of higher FSB)
+ get faster hard drive
+ get even more affordable DVD-RW recording