I clean the disk, registry and defreg every 3-4 days to 1.5 weeks depending on the amount of program downloading and removing I do. I also run a deep scan with 2-3 malware removal programs, I use Ad-Aware, MalwareBytes and Spybot Search and Destroy, to make sure nothing has slipped past by my defenses. I also monitor upgrades to all my programs with Secunia to ensure everything is up to date. I also regularly check for new BIOS and drivers and update as required. If I have notived any slow down, this usually cures it. I have something in excess of 8gb in my tool kit. If not I dig till I find conflicted programs or other causes. All this keeps my computer running fast and smooth. I will replacing my 2.9ghz dual core Athelon with a 3.0 quad core Phenom Black 64 and Win7 Ultimate 64 bit in a couple months. After that I'll install 2-4gb 1066mhz RAM boards, after removing the 4-1gb boards, then adding 2 more 4gb boards later. I may even try overclocking. My Gigabyte MoBo had an EasyTune utility for that and can store up to 8 different settings for the BIOS. Making it easy to switch from one to the other. I do wish it would accept DDR3 RAM. Oh well, next computer, lol.
Malware / Viruses are the most common cause of poor system performance, in my cases. Currently, it says most people have not reinstalled Windows, and I can easily see that. Most of the time, if they have an issue with their computer, they will sell it on Craigslist, and just go out and by a new one.
As for Hardware failure, why? Can't you just call Microsoft and tell them and prove them that your hardware changed?
Can be a pain, so I make a ghost copy of the system to a drive. I only use WD drives, & have enjoyed this feature for years. About every so many months (usually a year +/-) I'll reformat the drive & copy the back up to the computer. It already has the core software I want on it, doesn't have countless caches & hidden temps or things of that nature. No oopses from bad installs. Everything is fresh & clean. I just need to update the AVP, install any programs that haven't made it to the permanent copy & get going again.
It's just good maintenance for the computer, plus this is the time I really clean out the fans, coolers & all of those little spots.
In the past, I had to reinstall Windows 98 for hardware issues. Years later Reinstall Win XP because of errors I made during a registry "Clean Up". WhenI upgraded from Vista to Win 7, I had to reinstall Win 7 because of a software problem, but that was within the first week of my upgrade. I am pleased with Win 7 and satisfied with MS Updates.
My reason for re-installing Windows is that I had a pirated copy installed before on my desktop.
(I had no knowledge of this before).<div>
Then I decided to install a LEGAL copy and my computer, since then works fine now.
</div>In the past 6 months I have never seen any problem, Microsoft up-dates are installed automatic and so on.