Thanks for your response. I realize I didn't describe my system well. It is: ASUS M5A88-M mATX board, 8 gigs RAM (all 4 slots filled), 120 GB SSD boot drive with a 500 GB HHD, DVD read/write drive, Windows 10, in a Raidmax Hyperion case. The foot print is approximately 11"W X 15"H X 14"D. Was thinking something less wide, thus my concern about air flow.
When I built it, I was thinking I might be doing some home video editing and photos. That hasn't materialized. Mostly Quicken, web surfing, some streaming like YouTube. It has worked so well, I'm not ready to decommission it yet, figure it has more life in it. But...I now work from home fairly often so my home office desk space is at a premium.
Thanks,
Karl