Quote from: BTC_ISTANBUL on September 28, 2016, 08:25:16 PM

All the parts have life time in hours.

The fans have life time differing 15.000 hours to 36.000 hours.

The risers must be must be replaced, the life time is 500 days at average.

Motherboards lasts nearly 2 years.

The GPUs also have 2 years time if overclocked.

No problem with CPUs and/or rams so far.

While it is true all hardware will have some type of "life expectancy" or MTBF, I think your estimates are rather on the low end.

I agree with others that GPU cooling fans are probably the number one thing to go, but replacing these are fairly easy and economical with many exact-fit replacements available on eBay. The GPU's themselves keep running as long as they are cooled properly.

Risers, should last indefinitely, if there are issues with these it would be because of either physical damage or running too much current through them.

I have dedicated mining motherboards running since March 2013, and even have a few recycled ones (from personal builds) I am using from even earlier.

Of course, I like to perform routine maintenance on all of my rigs at least twice per year. This means taking the rig out of production, disassembling it and perform a thorough cleaning of all the components. This involves vacuuming and using canned air to clean heat-sinks and other hard to reach areas, re-seating all cables and components (except for CPU), and oiling and/or replacing any fans that are in need of more serious attention.

I don't mess with the CPU itself as risk of damaging pins is greater than any benefit. I might reapply some heat-sink compound between the CPU and the cooler, but once a CPU is socketed in a MB and running properly it is best to leave it alone. These two components are "Married forever" so to speak.

I think the other secret is to use some sort of quality surge suppression before the power supply to help minimize surges (especially in the Summer with T-Storms) and to ensure there is adequate ventilation around each rig. Except for physical damage, the other two leading causes of component failure is from heat and or electrical surges/shorts. By using quality risers, keeping rigs well ventilated and ensuring clean power goes a long way to getting long life out of your equipment.

For me this strategy paid off well, as while I sold off most of my GPUs from the Scrypt mining days, i had kept all the motherboards and most of my power supplies. So when Eth started to take off, I only had to pull my old components out of storage and buy new more efficient GPUs. For the most part, I only had to ROI on the GPUs as everything else had already been paid off from before. \

One last thing in keeping with this is spend the few extra $$ on a quality power supply. I read so many threads of people using these cheap power supplies and cringe. I have several 1000 watt Corsair units that again are 3-4 years old and in many cases still under warranty. Buying quality here not only leads to a more reliable and longer lasting PS, but also ensures the rest of your system lasts longer as well since clean stable power is key to everything else. Also, when buying a PS, size it appropriately, don't run 840 watts 24/7 out of a unit rated at 850 watts. While the better brands will handle it, I usually go with the 80% rule, which is the same as NEC for power circuits, and size my Power Supplies accordingly. So a 1000 watt unit I would only pull 800 watts from it when mining.