The 1.8GHZ P4 will be much cheaper than the current 1.7GHz in a couple of weeks
to quote Anand
For the most part, the Pentium 4 at 1.8GHz is able to remain competitive or offer greater performance than the Athlon 1.4. The real question happens to be at what cost, and unfortunately for Intel, the Pentium 4 can?t provide a suitable answer to that one. With cheaper 4-layer motherboards set to appear on the market and no longer a requirement for a new case (just a new PSU which you?ll need for an Athlon system as well if your unit is not powerful enough), the cost of upgrading to a Pentium 4 system isn?t as great as it once was but it?s still pretty significant. Considering the price of RDRAM in comparison to DDR SDRAM and the pricing gap between the Pentium 4 1.8 and the Athlon 1.4, it is still a very difficult sell for Intel although it is getting easier with each and every step.
The fastest P4 is faster than the faster 1.4GHz Tbird in more than just Quake. However, as Anand pointed out, this comes at a cost- a pretty heavy cost. At the end of the month Intel is planning large markdowns, some new DDR chipsets will be appearing for the P4 which may shake things up a bit and motherboards for the 478 pin 13um P4s are starting to appear.
On the AMD side we see new 735 and KT266 boards coming to the market to compete with the AMD761s. In the not too distant future nForce will appear and if it delivers what it promises AMD will have the backing of a killer chipset
If you have to buy today then i certainly think AMD offers the best value for money and heads of the P4 in a number of benchmarks, especially FPU intensive ones. If you can wait 3-4 weeks then the field is likely to be somewhat levelled.