GLM-5.3 320B (18B active) Flash

User reports running GLM-5.3 Flash on an RTX PRO 6000 Max-Q with DDR4 system memory at roughly 35 tok/s with 512K context. No engine, quant or KV cache format is stated; the DDR4 mention implies weights or KV cache are partly served from system RAM. The user asks whether upgrading to DDR5, at a cost of 6k EUR, would be worth it if it reaches about 50 tok/s, and asks for others' experience.