I tried it, just so I can't blame myself for not having tried, and no joy. My Windows is much faster (I guess it helps memory management of the 64 bit Athlons), it boots in 10 seconds, but Poser doesn't change, it still can't stand using more than 1.5 GB...

BTW, stewer, if you happen to read this, I forgot to say that while Poser is in his loop, if you click on "Cancel", it will show "Canceling...", CPU will drop at 0% and that's all she said.
I've waited a whole night, it never finished "Canceling".

So this loop is:

• Showing the background color in the preview window (always clears the preview).
• Using CPU at 100% but doesn't prevent Poser form refreshing, unlike the true rendering, when Poser only refreshes after having drawn a new bucketfull.
• You can drag the little render progress window freely around, which also shows Poser isn't doing anything serious.
• Of course Poser never renders the slightest bucket.
• Can be canceled, without avail: CPU drops (almost at once) to 0%, memory usage stays high (no memory freed), and the message "cancelling" never goes away.
• This happens when memory usage reaches between 1.5-1.6 GB while initializing.

On the contrary, a "good" render will do the following: (YMMV)

• Show the preview untill the first bucket arrives, replacing the rest of the pic with the background color.
• Poser refreshes only when it draws a new bucket. Between buckets it doesn't refresh.
• The little render progress window can only be moved in the fraction of the second Poser draws a bucket (sometimes). The rest (most) of the time it's pretty well stuck.
• When you click "Cancel", well, it cancels! It takes some time, but it aborts the render.

My usual render settings: Raytracing (2 rays), displacement, shadows, min. shading rate 0.20.
No texture filtering, no smoothing.
Pics always using AO and only raytraced shadows (no shadow maps).