I was wondering if that was a red herring. I would figure if the resistance was an issue the computer would probably not even turn on. It is difficult to impossible to get schematics for anything modern unfortunately but I had hopes. Sad thing is I had a very nice spec gaming pc but it went on me also and I got rid of it as I couldn't be sure that placing parts from it in a build pc wouldn't take out the motherboard. This is actually my older PC I'm trying to figure out at the moment. I have no other PCs whatsoever so there isn't much I can do. The more I hear from you guys the more I suspect a software or hardware issue.
Well, this attitude won't help you much.
Take a systematic approach and start eliminating the possible problem sources one by one and start with the software. Did this problem start recently? If yes, what happened at that time? Did anything change? (= new software installed, hardware replaced, etc.). Does undoing the change fix the problem? If it is not a recent issue, has it always been like that? Did you check for viruses, malware, etc.?
If even a clean install of the OS with up to date drivers for everything doesn't fix the problem,
then you can start suspecting hardware. Run disk test (failing disk drives can cause all sorts of problems), run memory test (failing RAM ditto), verify that all fans are spinning and are dust free, verify that the CPU heatsink is seated correctly (overheating CPU = crash).
If you don't want to reinstall the OS, then you can download some Linux distribution and install that on a spare drive (or a free partition). You can also run some versions from a CD or USB stick. Boot Linux and try to browse, play videos, basically stress the machine a bit - if it runs stable with Linux but crashes in Windows, well, that's not a hardware problem then. If it causes problems in Linux too, then at least you will get more information about what is causing it in most cases - Linux will tell you in the system logs (also google the 'dmesg' command).
If all that is done and you still haven't found the problem, then you will need to find someone who you can swap components with if you don't have another PC. E.g. if you want to eliminate that it is the power supply, borrow a known good supply from a friend and try it in your machine. (don't do it in reverse because if your supply is faulty, it could in the worst case fry your friend's PC). If the machine runs stable with that, THEN go buy a new supply. That's how you troubleshoot a PC supply problems and
not by sticking multimeter probes into output and measuring random stuff without having any ideas of how such supply works.
Same for motherboard, CPU, etc.
Also, if you can, update at least to Windows 7. Vista is both long out of support (so it is also a security problem because you won't get updates anymore) and is infamous for random crashes and problems. We had several DELL workstations at work which were perfectly fine with XP and Windows 7 but never ran stable with Vista - random freezes, crashes, what not. I don't think I have ever seen a stable machine with Vista on it, in fact.
If this is not something you are willing to do, then, I am afraid, you will need to spend some money and bring in a specialist - there are plenty of PC repair shops around. This is not something someone on the forum will be able to troubleshoot for you.
BTW, schematics for common PC supplies are available but your don't really need schematics to repair one if you were so inclined - most of them work in more or less the same way. On the other hand, that is
not a job for someone who doesn't know how it works and that there are dangerous voltages inside even if the supply is unplugged - the primary side capacitor can blast you with some 300 volts if you poke your fingers or multimeter probes in the wrong place. With plenty enough current to kill on the spot you if you are unlucky. The other thing is that there is little point in repairing these things unless it is some special, non-standard form factor that is difficult to find. A new one will likely cost you less than the replacement components and the time wasted troubleshooting the old crappy one. However, all this is not relevant until you eliminate all other possible problems using the method above. Otherwise you are literally just shooting in the dark and wasting time on stuff that in all likeliness is not the problem.