some say you dont "need it" but i would recommend it. Its like a computer, the OEM heatsink/fan work but a zalman or something is always recommended. The more you can keep your temps in line, the better it is for durability and long term life.
But if you dont plan on tracking, a 19 or 25 row should be fine. maybe a 25 row with a thermostatic plate since your down in TX.
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