how much difference does kv cache quants even make?

I currently run qwen flash next 3.8 iq3xxs via strata (like almost everyone lol) and I currently have kv cache at q8 with 262k ctx. Ive never actually tried any other quant and dont know how big the difference even is. Id like to have a bit more context (like 300-400k) but it doesnt fit my ram then.

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I currently run qwen flash next 3.8 iq3xxs via strata (like almost everyone lol) and I currently have kv cache at q8 with 262k ctx. Ive never actually tried any other quant and dont know how big the difference even is. Id like to have a bit more context (like 300-400k) but it doesnt fit my ram then.