Going from Pentium 4 to Pentium D?

It depends on what P4 chip you currently have. The Pentium Ds all use the LGA 775 socket. The last of the P4s use that socket, but the very first P4s used Socket 478. The two are incompatible with each other. If you know the make and model of your motherboard you can easily look up which socket is on it online, but you can download a free utility called CPU-Z that will also tell you:

http://download.cnet.com/CPU-Z/3000-2086_4-1005042...

If you have a newer, faster Pentium 4 HT that uses the LGA 775 socket then you should have no problem switching to a Pentium D. Just make sure that your motherboard's manufacturer lists that as a CPU choice. If you happened to get a very early motherboard that was designed for LGA 775 but came out before the Pentium D chips came out, you may need a BIOS upgrade for it to be able to recognize a Pentium D.

I doubt you'll need to upgrade the PSU, but if the system has a power-hungry graphics card you might. The P4 HT processors use anywhere from 65W to 115W of power. Determine how much power your current CPU is using by searching its name in this list:

http://en.wikipedia.org/wiki/List_of_Intel_Pentium...

The Pentium Ds use either 85W or 130W, depending on the model:

http://en.wikipedia.org/wiki/List_of_Intel_Pentium...

So obviously if your current P4 is using 115W and you're thinking about getting an 85W P-D there will be no power problem at all, not even with a 130W chip, in my opinion. But if you are wanting to go from a 65W processor to one with a 130W rating, that might be a different story. But 400W should be enough unless you have a fast video card in the system. It's the same story for the cooling issue -- a CPU that draws more power runs hotter. But if you're buying a Pentium D it should come with its own Intel factory cooler on it. I don't think they are/were sold as bare chips, though I skipped from a Pentium 4 recently to a Core i7, so I've never actually seen a Pentium D setup. Well, sorry that's not much help, but I figured everyone else would simply tell you to junk the system, so that's what I can offer. Good luck with the upgrade!

Let's begin with the easiest to answer question. Your power supply is probably fine for your upgrade. The processor doesn't really impact the draw on the PS. The motherboard should have a supported CPU list. If the P4D is supported swapping one in should be fine.

If you really want to check if the PS is good enough look at the label on the side and read the +12V area. You need to have close to 30W in the +12V, which in the linked is a split rail of 18W on each, meaning it has a total of 36W on the +12V rails, which is plenty.

http://www.tigerdirect.com/include/AddCartfromGall...

Now, the cooling system. If the new processor comes with a stock heat sink and fan then it is adequate and good enough for maintaining the warranty which is the strongest argument for any level of cooling. If it wasn't good enough then they wouldn't include it. If you are going to reuse the original fan from the Pentium it will probably be fine as well, but make sure you completely clean all thermal paste from it and use new thermal compound to ensure good heat transfer and proper cooling. One of the more common causes of failure is the lack of good contact or improper installation.

I'm assuming since you willingly admit this is old hardware that you have a socket 478 motherboard. As a side project it's fine to do what you are doing. If you intend to use it as a gaming or video editing machine it may not yield much of an improvement but you will be going from a single core to a dual core. This should give you a good boost.

So, go forth with your project. Don't worry so much about power. If you are not using a stock cooler with the CPU then consider an aftermarket cooler but make sure there is room in the case to install it and also consider getting thermal compound to mount it.

I hope that's enough to help you make your decision! Good luck!

Your power supply is fine. At most, the Pentium D is going to pull 40W more than the P4, which isn't an issue unless you're already pushing that power supply's limits.

Make sure the motherboard can accept a Pentium D. It probably can, but not all motherboards BIOS' were upgraded for the PD. If your PC was originally offered with a PD option, you're fine.

Some PDs have power requirements no higher than P4s, but it varies. Your best bet is to look up the exact processor models at a site like http://cpu-world.com/ or http://ark.intel.com/ and compare actual TDP ratings for the processors.

An aftermarket cooler couldn't hurt. Either way, make sure you have new thermal compound available to afix the heatsink to the new processor.

Pentium D, it helps twin processor cores on a single CPU die, meaning it somewhat is quickly and sturdy for multi-tasking. A twin center processor is extra clever at working different applications. Like applications that take a hundred% of your cpu and your gadget will become unresponsive on a single center gadget, twin center keeps to be responsive via fact of the different center.

Using a processor of the same series does not requires next-generation hardwares and items like power supply if they work normally and according to its technical specifications.

And what about power consumption? Would I need a better power supply (currently have a 400W PSU)?

400W psu more than enougf for P-D

Throw it away and GO with amd sempron for a side work as it is the cheapest cpu for $35

Just buy a latest PC it would cost less than buying year to year