5-year warranty on P/S?
However; the motherboard could be the "weak link", as warranty is limited to 3 years. Probably easiest to check the mobo for any sign of leaking or bulged capacitors.
I calculate from your listed power-on usage, a total "ballpark" figure of 23400 hours.
Assuming that the capacitors were originally meant for 2000 hours @ 105°C, this would work out to approximately 32000 hours @ 65°C. If the power fluctuates in the building it is in, that figure would be reduced.
I would guess that you could have a year of usage left in it, yet i am uncertain. I lack much information specific to your computer's issues. The brand and series of capacitor will effect those calculations also. Bear in mind that electrolytic capacitors can fail without any outward sign, although nowhere nearly as common. Damaged components usually are found nearest the most significant thermal-zones. A non-contact infrared thermometer has been a guide to me for finding how bad a thermal zone can get. I do this during a "memtest" to evaluate a "close-to" worst-case scenario.
Back to BIOS; if the system exhibits "instabilities" or "failure", that is not a good circumstance to update the BIOS. Call it a "last-resort", perhaps, on a setup with a minimum of components?
Using SLI? If so, use a low-powered card of the same chipmaker (optional) for testing.
PS: Looking at the comments on newegg concerning that BFG (defunct?) P/S, of those whom have experienced failure, a large percentage have experienced catastrophic failure, at least according to their claims.
PPS: That "claim" of 1000 Watts could be another example of corporate "free-speech". Think of how HDD/SDD/etc. manufacturers henke with their math in defining a "Gigabyte", or a "Terabyte". 1000 Watts may have been a theoretical maximum, not a real-world maximum.
This does seem like an extreme opinion ordinarily disregarded. It would be interesting to see some high-res pictures of the internals on that puppy to confirm or deny.
Don't go opening it if you are not familliar with the risks and how to alleviate those risks.
To me, "modular" can equal "voltage drop". Avoid use of these connectors if the ends become discolored.