Saw this awhile back but it didnt register in my pea brain for awhile .. till today as I was surfing during coffee break..

Anyhow this is benchmarking for render times vs gpu's etc inside yes blender, but the information should be somewhat informative for purchasing if your interested in such things.   (me I purchase what I can afford and upgrade when things get annoyingly slow ^^)

https://opendata.blender.org/query/fastest-gpu

the biggest takeaway from this right now is that the newest generation gpu's 2080ti maxed out are faster then the titan v's
 (not by much but if your looking for value for money you might be interested)

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