Couple of thoughts from other perspective
> Right, let's take this message apart, and respond to each element in turn.
Q: With so many expectations associated with Windows 8 and the unexpected affordability of its price tag, options abound for its implementation.
> True, but do you actually need any of the new features it packs?
> And keep in mind that newer editions of processors have additional instructions baked in; when ambling along on old hardware the new OS will resort to breaking up the newer one-step instruction onto several steps which the older CPU can handle. That takes extra CPU cycles, hence time, and can considerably slow down the new OS on old hardware.
Q: Microsoft has made no secret of its wish to have one system to rule them all, but if that is the case, we really need Windows 8 to displace the XP systems out there.
> May be the case that Microsoft has a wish, but do you need to comply?
> In other words, you resisted the urge to get Vista and Seven ...
> ... but now you've changed your mind, and want to assist Microsoft in displacing the OS which you have used happily for perhaps ten or so years.
Q: So, here is my question ... I have a 2.8Ghz, Pentium 4 with 1.5GB of RAM and a 80GB hard drive.
> That to me sounds like an eight or ten year old computer?
> First thought which comes to mind is that my time-honoured Pentium 4 2.8GHz consumes 12 Watts when off (that's not sleep), and around 80Watts when running. Is it connected to a classic CRT display (my 19" screen used in the order of 250Watts!!), or do you use an LCD TFT flatscreen (mine uses 70Watts)? In comparison, the new Notebook uses 35Watts when streaming video full screen - that's about one quarter of the energy.
> Before you do anything else, get your hand on a power monitor - that's a smallish appliance where you plug the equipment in, then plug the monitor into the power socket and read things like current usage in Watts and accumulated usage over a period of typical use in kWh. Multiply with cost per kWh and you'll know how much running the computer will set you back year after year.
> Note though that not all power monitors are equally suitable, and comparison testing by a guy at the computer club showed that higher price did not equal better performance - one of the cheaper units (costing in the order of 25GBP/ 30EUR/ 40USD) from a specialist electronics chain gave the most accurate readings when compared to calibrated equipment in the laboratory. Keep in mind that their readings in the lowest range are not always linear; you can get around this by measuring the equipment in tandem with a known load in the order of half an ampere - that's a 60W light bulb where they use 110V, or a 100W bulb where they use 240V such as in the UK).
Q: It has a very good sound card and basic video card.
> Sound cards these days are all rather good, even the on-board sound is good stereo; the actual sound you hear depends on the acoustic properties of your listening environment, the placement of the speakers, and the quality of those speakers. A comparison comes to mind with a place I worked, they'd bought really good VDUs for their CAD software, to find that ten years later an off the shelf screen had better performance, higher resolution, and then there were the savings on energy ... .
Q: I really want to do something with it, such as turning it into a jukebox or a basic PC for my son, but I really have to replace the OS.
> Like me, you may be reluctant to throw something out which still works - so do my 1979 bicycle, our 1977 stereo, 1983 washing machine, the 1985 CRT TV and my father's 1987 car. Especially that TV was renowned for its great speakers back then; but my new LED TV uses one-tenth the energy, has a much clearer picture, and if excellent sound is required it can be heard via the stereo - which has noticeably better speakers than the built-in TV ones.
> As a jukebox it would be running many hours on end, and comparing my Pentium 4's Watts used with the recent notebook there would be a saving in the order of 75%.
> The old XP box with 19"CRT screen used approx. 8kWh per day = about 3000 kWh per year when running full time as a jukebox (even though you might not listen full time, many are reluctant to sit through the boot sequence when they want to hear something on their jukebox, hence leave the thing running if only to respond to the remote control). Based on my measurements, the notebook would save in the order of 2250kWh of electricity which, including all levies and taxes costs 500GBP/ 625EUR/ 800USD - hey, looks like you've just saved yourself a brand new notebook each year by properly recycling your old XP box with CRT. Yes, the combo old XP box with LCD TFT would only save one third that amount per year, and you may remember to switch things off at night, but the savings in energy are still quite noteworthy compared to the price of a new notebook with i5-class CPU.
> As a basic PC for your son: would that be in addition to his school computer? Most schools in this area require a specific level of hardware and portability, so it can be taken to school and also used for homework. Then there are schools which have taken weight into account and require a tablet computer, usually an iPad. Needless to state that experience using Windows 8 on a 'non-touch' computer is of little use when using an iPad in class.
> Incidentally, have you considered adding a limited user account to one of your other computers, for your son to gain experience with Windows 8? And would a 'non-touch' computer actually allow him to gain the optimal experience which you so crave him to get? (This is a sentiment which I fully support, which is why I have taken the time to reply)
Q: Can I install Windows 8 and revitalize my machine and, if so, what else do I need and what should I expect?
> Revitalizing an older computer can be as simple as copying all files you want to keep, noting all software you actually use and making sure you have the installation files and any license codes for it, plus drivers for any hardware connected, then re-installing the operating system and doing a full format when prompted during the process - it is amazing how many unused bits there are on a computer once it has been used for just one year, and how much faster your old computer will run afterwards. Do find out whether your old computer can easily be restored from the restore partition, some could not yet that long ago!!
> Windows XP SP3 will receive security updates for another 18 months - according to their website till 8 April 2014, and experience in the past has shown that security vendors will keep supporting their solutions for several years thereafter - there may be a so far un-noticed issue, but it can be blocked by the Anti-Virus etc software.
> Should you decide that the extra electricity used by your old XP computer upgraded to Win8 is of no concern, but that not having security updates for Windows XP is a really serious issue, then you could nearer the time consider installing Linux - there are resources out there on the interweb which will help you determine whether there are drivers for all your hardware components, and assist in selecting the version which is right for your needs. Ubuntu on an USB-drive sounds like a decent starting place to get the feel, there are other so called "Live Distros" out there, bing, google and ixquick are your knowledgeable friends there.
Q: I am sure there are many other people out there wondering the same thing.
> I, for one, also wondered, and decided - having found that my Netbook (Win7 starter-edition Atom 1.6GHz 2GB 500GB) performed faster than my WinXP sp3 Pentium 2.8GHZ machine - to replace the Pentium with a Notebook running Windows 7 on an i5-2500 series CPU and 4GB ram. That computer runs circles around my old Pentium, even when doing simple things like viewing webpages or starting a word processor.
> Come to think of the 80GB HD capacity: windows keeps lots of files and several restore points on the hard disk; the recently re-installed netbook does not contain user documents (they're kept on a thumb-drive to use on several computers), yet some 45 GB is already in use just by the OS and some software; considering that windows performance slows down when there is less than one third free disk capacity, an 80GB hard disk is likely too small when you also want to keep music on it to use as a jukebox; have you considered a separate NAS device? Network Attached Storage devices act as a central repository for any files which you want to access from one of several computers on the home network, and would take up far less space than your old XP box with screen.
Q: Can you help?
> Hope this is of help?
> Not at all, it was my pleasure entirely .