You can still get top mount cases, but let me tell you after switching to a bottom mount case (the coolermaster CM690) I will NEVER use a top mount again ever. I mean, I understand what your saying-you would think that would happen, but it doesn't work that way. In a properly built case like the CM690, with a quality PSU the bottom fan of the PSU sucks in cool air in from the bottom, and out the back, leaving little, to no heat, entering the case. While a top mount case, that bottom fan, is pulling already heated air from inside the case, blowing it over hot components and out the back-increaseing your chances that the PSU will overheat, and therefore heat up the inside of the case.
From what I have seen, I see very few, if any, PSUs, at least not high quality ones such as Coolermaster, Antec, Corsair, or OCZ models, that have the fan on the top of the PSU, theyre all on the bottom, so they can be mounted on a bottom or top mount case and suck air in and out.
Primary system: Motherboard: ASUS M4A89GTD PRO/USB3, Processor: AMD Phenom II x4 945, Memory: 16 gigs of Patriot G2 DDR3 1600, Video: AMD Sapphire Nitro R9 380, Storage: 1 WD 500 gig HD, 1 Hitachi 500 gig HD, and Power supply: Coolermaster 750 watt, OS: Windows 10 64 bit.
Media Center: Motherboard: Gigabyte mp61p-S3, Processor: AMD Athlon 64 x2 6000+, Memory: 6 gigs Patriot DDR2 800, Video: Gigabyte GeForce GT730, Storage: 500 gig Hitachi, PSU: Seasonic M1211 620W full modular, OS: Windows 10.
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