Overclocking a GPU is an inexact art. It can be both fun and frustrating! If you decide to do it, be prepared to do some research, have some monitoring and benchmark apps and have fairly large amounts of time to test things out. Newer versions of MSI Afterburner have a built-in overclocking tool that's fairly automatic and will get you close to what you could attain doing it manually quicker, which should be good enough for most. It's easy and safe.
The thing is, every card is slightly different from every other card. They can be the same brand and model. Plugged into the same PC. One will OC great, one won't. It's just the nature of it.
Boosting the clocks, you'll have to pay close attention to the heat generated. Cooling is prolly the single worst limiter to an overclock. Card gets hot, it either slows down on safety or it flat out crashes. Now you're starting over. Watch the temps and clocks with Afterburner so you know what's happening. Keep notes. You might need to add some voltage to get to the clocks you want. Maybe you can do that - - maybe you can't! If the card limits it in it's bios you're generally screwed as it physically won't let you get there. If you can, Afterburner has settings for that.
Once you start into this you have to go in tiny increments boosting a few ticks at a time. Bump up a few ticks, run benchmark, lather, rinse, repeat. Time consuming. You're either gonna get to a point where there's too much heat or you start getting artifacts like flashes or odd lines or both. At that point you need to back it off a few ticks. Keep testing to make sure it's stable. I like to run the Unigine Valley benchmark on a loop for at least an hour once I get something that doesn't act like it's gonna mess up.
If it's an older or used card be sure to replace the thermal paste on the GPU. It'll help with the cooling and thus, performance. Find a tear down vid for your card so you don't break anything in the process.
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