I'm moved to using imgur.com because of changes at such sites.
http://www.hwcompare.com/137/radeon-hd-4650-512mb-vs-radeon-hd-5670/ tells me this card is about 55 Watts which isn't much more than a stock card in many desktops. Why the PSU change?
As to the slot coverage I'd wait till your 4650 shows up.
Bob
I have only 1 PCIex16 and 1 PCIe1 slots. Just bought a graphics card [Sapphire ATI Radeon HD 4650 512 MB Low Profile] and a usb3.0 card that will go into PCIe1 slot. I think the graphics card in the x16 will overhang the x1. Fan. Is there some kind of extension that I could use in the x1 slot to move it over 1 position? A cable, adapter? I have a new 450W power supply, so thats not an issue. Here is a pic.
https://www.flickr.com/photos/syncman1/16526314288/

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