SFF

Thank you! The Dell SFF can only hold one 3.5 inch HDD right?

Yeah, just one. Here is the service manual: https://www.dell.com/support/manuals/en-us/optiplex-7070-sff...

I got a refurbished unit for $180 last year, using this deal (now expired): https://slickdeals.net/f/17490348-dell-coupon-50-off-refurbi...