Allo tq530
I'm not fully 'savvy' with all the different PC cases, but lots of folks here recommend the 'Antec 900' for size, ease of working inside and coolness, both temperature and looks
As for the power supply wattage, that would depend on exactly what motherboard, processor (CPU), graphics card, RAM and other bits that are fitted. Usually, it's the last part to be thought about, cos you need all the above bits to work out what's needed to power them all

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