Uh, Creemail, clarify what you're saying. It's possible to:
Take a VGA output, & use a VGA to DVI-A cable. You're still outputting 15-pin analog, but DVI can handle both.
It's also possible to:
Take a DVI-D output, & use a DVI to HDMI cable. The signaling information for DVI (digital) and HDMI are the same, after all.
It is NOT possible to pass an analog VGA signal onto a digital HDMI connector with use of an intermediate VGA-DVI adapter.