Most "professional" miners were actually undervolting to keep the power consumption down so it's really not that bad as long as the price is right.
Anecdata but, 3 years ago I got an old mining RX 580 4GB for ~120 CAD (about a $100). That card can run almost everything at 1080p and has been used a lot ever since.
I've got over 100,000 of those RX470,480,570,580 8gb cards running for 24/7 years. It is a total farce that they go bad over time.
Not only were ours undervolted, but also individually tuned for best performance/watt. A very difficult thing to do at my scale since the failure mode is a full machine crash.
Only thing that really degrades is the paste on the heatsink and that's fairly easy to fix.
The largest challenge was tuning the cards for best efficiency.
Next up is just tracking inventory, making changes to the system, etc... this is over 8k individual computers in multiple data centers.
We also added a different class of hardware which was blade based... which increased the individual computers significantly. Ended up with a very cool iPXE boot solution for that.
I also built some pretty cool software to manage it all. It runs on the concept that each machine is an individual worker that knows how to self-heal itself. Even just distributing the software to so many machines reliably, is a challenge.
It's more temperature variation that kills cards. In a conventional mining setup thermals are monitored and accounted for. A card running at 70C 24/7 will last a long time. Longer than a card that is constantly bouncing around in temperature.
Also untrue. My cards have been running for years in shipping containers that are outdoors and go through full 4 seasons (winter snows to summer heats).
Edit: power supplies on the other hand... are a mess. Mostly hand soldered in China... they fail randomly due to the environment they run in. Sometimes, they "die", let rest for a day or two and then fire back up and run just fine.
Temperature changes outside don't translate to temperature changes on the die. If the cards are running 24/7 there will be no thermal shock to speak of since they are always generating heat.
Various machines reboot randomly all the time. Given the amount of direct outdoor airflow that we push through the machines (we don't have fans on the GPUs), as soon as the GPUs stop running, they cool down very very quickly. That is the 'shock' you're looking for.
Why do they reboot? We run on the edge of peak OC tuning performance by default and I've built an automated tuner which downclocks individual cards. This way, they get more stable over time, while maintaining their best possible performance.
Occasionally, we would reset the tunings and then let them auto tune back... this accounted for the seasonal variances because hotter cards are more prone to crashing.
How often does the average machine reboot? If it's less often than 24 hours you're still putting the card under less thermal stress than someone who games for a half hour every evening. I'd buy your used GPU over a gamer's used GPU
Sometimes it can reboot 50+ times in a row. Each box has 12 gpus, so if I reset the tuning for the box, it can take a while to find the optimal settings because the voltage/clock tuning steps are very granular.
Again, this isn't an actual issue and I have the data to prove it.
It may still be a lot less 'shock' than normal use, where players have a 15 minute round, then low use for a couple minutes, etc, for hours.. and then turn the card off.
Thermal cycling is known to be bad for electronics-- this is well studied and documented. Sustained high temperatures are also bad, but it's only really bad when the temperatures are really high.
I'm pretty sure my cards have gone through all extreme different load situations that you could possibly make up in your head.
Certainly, thermal cycling can be an issue for electronics in general, but my experience with these specific cards says that it isn't an issue at all. At least certainly not as much as something that should dictate purchasing 'miner' cards or not.
Miners overclock and overvolt the memory because there's a substantial performance advantage to doing so with little efficiency loss. This rapidly ages the memory.
Also, 70c is well into the temperature range that will significantly age capacitors.
My point stands: a capacitor that spends most of its life at room temperature except for a few hours at ~60c is going to last significantly longer than a mining card which spends 24x7 at 60-70c, regardless of temperature rating.
Untrue, forcing more usage on a card while mining will immensely increase power usage whilst hardly improving hashrate. Mining GPUs are undervolted and arguably will be in better condition than a hardcore gamer's card.
Is this actually a problem, besides needing to replace a cheap fan? If the fans go out, they just maintain thermal limit. These aren't like old cards, where they would melt.
Replacing a GPU fan is generally a lot more involved than other PC fans. Some you have to take the GPU apart (sometimes involving glue) and some fans are harder to get than others. I'd say it's harder than building the PC itself, but still fairly easy.
