Vista Ultimate w/SP1 recognizing more memory

I recently installed the 32bit Vista Ultimate on my own built ASUS P5K deluxe wifi board with 4GB DDR2 memory. A few days after the initial install Microsoft allowed me to install SP1. This was about 10 days ago. Immediately after the SP1 install I noticed that Vista recognized the total 4GB Ram, and before it would not. Microsoft tells me that SP1 not only recognizes 4GB memory, but it now has the capability to use up to 4GB memory. Is this true, or did I misunderstand Microsoft?

32 bit limitations still apply to all 32 bit operating systems - The fundamantals have not changed. The change is simply that Vista SP1 displays the installed amount of RAM, rather than what is available for use. The rumor is that Microsoft made this change because of pressure from OEM manufacturers who disliked having to answer a seemingly endless stream of "...my computer only shows 3.25GB instead of the 4GB I paid for..." phone calls into their support centers. Task Manager and/or the Performance utility will show actual available and usage.