Hard drive – first off, adding a hard drive can be somewhat problematic depending on the age of the computer. Specifically, the IDE interface on an older computer, may not support (most likely won’t) the newer hard drives, and there can be issues with the bios…

Motherboard… If a computer is more than a couple of years old, buying a motherboard will also entail a new processor and possibly memory… again depending. Especially given that upgrading a motherboard without upgrading bus speed and memory speed is rather like updating the chassis of the car but sticking your old 4 cylinder back in… Plus… not all users would feel comfortable with doing what is effecitively an engine rebuild on their computer. Add in that, depending on what the user needs, by the time you spend that money, Wal-Mart has a pretty decent system for $450… add in time and effort… and… well you get the idea…

Swapping processors… this one is doable, however, the end user had better have a pretty good idea of what they are doing. Upgrade a p2 or p3 processor probably isn’t going to give the performance boost that you are looking for…

Monitor – Eye candy is always good…

If your computer is truly sluggish, and you just don’t want to part with it, or go through the pain of moving your files to a new system… based on my 30+ years in the industry, here are thing you can and should do, and in most cases will have your system running like new or better:

1. More memory… Yep… This is something you MUST do… the more RAM you have, the less the OS has to swap stuff out to “fake ram” on the hard drive. This takes load off your hard drive, makes programs and file access faster AND, the more of a program that will fit into RAM, the faster it runs, because there is NO hard drive/buss subsystem yet that can keep up with ram… ram is an order of magnitude or two faster…

2. Video – A HUGE part of windows is the display portion, it affects everything… feel free to spend as much money(within reason) on a good video card as you like. $100 will get you a pretty decent card, with lots of independent memory on it, and hi speeds, better resolution et all. Video cards are important, them more the card can process independently of your main process the faster everything is… This will truly make your computer run tons faster…

3. Clean up your computer – Windows has an invisible, internal database that tracks EVERYTHING. If you have software you aren’t using, get rid of it, One piece of software can have 100’s or even 1000’s of entries in this database, and the larger it is, the harder windows has to work to find stuff. Clean off your desktop – you heard me, clutter on the desktop chews up ram(I won’t go into why, but trust me it does). You should NEVER have programs installed on the desktop. Nor should you really have files…. shortcuts to folders or programs is fine, but the rest. NO NO NO… and if it isn’t something you NEED, get it off your desktop. Defrag your hard drive… yes I know this is tedious, and time consuming, but really… if you do it regularly, it takes less time… and you CAN schedule it to do it while you sleep.

Other things that you can and should do… There is a service that is installed by default on Windows. It is called the indexer service. What it does is keep track of every file you have on your computer, and saves this in a database, making it faster to search for something. Problem is… it is a hog… if you aren’t in the habit of loosing files on your computer… shut this thing off… you can wait a few extra seconds to find something you truly need…

Autostart programs… this is a person by person call… but if you have itumes, yahoo messenger, msn messenger, oultook, myspace im, quickfind, outlook, the weather channel, and god knows what else starting up when you boot your computer, on top of things that NEED to be there… it will not only take forever to boot, but you have lost a considerble chunk of ram AND processing power to stuff running in the backgroud. Examine the things that start up when the computer does and only run what is ESSENTIAl to your computing habits.

Lastly…. scan your system regularly for adware/spyware and other crap that just accumulates. I recommend once a week, and suggest using Ad-Aware, SpyBot search and destory and XoftSpy… between the three of these programs… you will get rid of 99% of everything…

So… Add RAM, upgrade your Video, clean your computer… and it will run better… Oh and on a positive note… if/when you DO buy another computer… well, the ram might be throw away, but the video card you can probably move to the new computer… and save some money there…

Happy puting…

With regard mobo’s, if you didn’t build your own PC you will more than likely fall into the problem of the PC case just not being able to fit a different design motherboard due to the layout of the case.
Also, keep in mind that if you upgrade the mobo you are likely to have to upgrade the RAM, CPU and PSU at the same time and it can quickly become expensive.