<The H780 supply is about 3 inches wide IIRC and mounts beside the card cage <That would make it a couple inches wider than the TU58EX. <Dan More like 5" when you add casing. I have a 780+backplane. The Rackmount BA11-M is 3.5h x 19w x 18.5d (the depth is possibly inaccurate) The destop version is a little larger for prettyness. The BA11-VA 3.5h x 13w x 13.5d the H780 ps alone 5.5"W3.3hx14.625L The BA11M however will take a lot more cards though but is very noisy. Allison