After having a P3 1Ghz for over 3 years, I've decided I want to upgrade. Now, I'm aiming for 3Ghz as of right now, and I have different choices for this. I'm obviously going with Intel. We have the following: INTEL P4 PRESCOTT 3.0EG/800/1M/S478 INTEL P4 530J HT 3.0G/800/1M/LGA775 The difference in price between them is not significant. My question is, is it worth it to go with Socket 775? I believe, if I'm not mistaken, that the new line of 775 processors are 64 bit, much like the athlon64's. This could come in handy in the future. I'm aware that yes, Intel will probably drop its 478 line of P4s soon, and work solely on 775, and that would mean possibilities of upgrading would be limited. However, I will probably not upgrade again for some time, so this is no problem for me. And finally, is the 775 line better for speed when compared to the same clockspeed in 478? And is it worth it to buy a probably more expensive 775 supporting motherboard to use this processor?

Things to consider: The 478 is more friendly to overclocking if you don't intend to get a prescott above 3.2. The 775 has a faster bus and, depending on which core you go with (915 vs. 925) faster RAM in the form of DDR2 on the 925. The 64bit P4 isn't out yet and the formfactor is still to be determined, but it likely will be the socket T. As you pointed out the 775 is the friendlier for future upgrades and it sports the latest graphics interface PCI-Express. You might feel that upgrades are of no importance now, but you also don't want to have to shell out for a completely new system AGAIN two years from now. This is why I chose the 775 over the 478. You're right, the prices aren't that different, so why go with last years components? As for the mobo price, you can get a really good one for around $120US. My Asus I paid $127 for and I'm exstatic. Go with the 775 purely for future considerations, you never know how you may feel down the road. ASUS P5GD1 P-4 3.4 SOCKET 775 1G Corsaire PC400 ABIT RX600SE 256MB PCI-E

My p4 540 reports as x86-64. em64t capable. The 3.2 is as low as $195 now. No complaints with this board either. Tried a chaintech 915, but too many problems, it hung, the pci sockets didn't line up with the case, and the onboard sound cracked and popped. No problems so far with this new intel board. intel D925XCV 1024 mb pc 5400 ddr2 geforce 6600 gt oc pcie Maxtor SATA 120

Got myself a p4 530j (3.0GHz) and Intel915 (the 915 boards also support DDr2 and PCI-E) board, it also reports EMT64 capability on sisoft sandra (wasn't aware of this, might get xp64 beta)! Runs very stably, would recommend going the LGA775 route :) P4 LGA775 3.0GHz 2x256Mb DDR2 533MHz XFX 6800GT PCI-E

hey guys the p4 500 series (socket775) suports em64 wich means emulated 64 bit but the newer 600 series suports real 64 bit wich in many tests is better than amds 64 bit amd only beats p4 600 series in some games all other tests p4 wins so my adwice is go for the p4 600 series

yeah I noticed today the 6 series are the full 64-bit processor. So presumably you would gain little benefit from running a 64-bit OS on a processor that only emulates 64 bit? Btw, I've got DEP enabled on my chip, is this equivalent to the NX technology on athlon 64's? P4 LGA775 3.0GHz 2x256Mb DDR2 533MHz XFX 6800GT PCI-E