The nice thing about reference model gpus is that you are assured a certainty level of quality becuase they are built to the gpu companies requirements. In many cases all the way down to specific components on the gpu.
Non reference gpus can be built above or below original quality levels. Luckily normally they are an improvement over reference but some companies have been caught using cheaper components on their non ref gpus in the past. Not cheap enough to effect day to day performance but overclocking suffered.
Passmark- Misleading newbs since 1998.
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