Well I guess that qualifies as fairly new hardware.
For what it's worth, my setup (full-time HTPC) is an Asus M2A-VM Mobo, AMD Sempron, and integrated ATI X1250 graphics. I switched to the Asus about a year ago that from a 3 year old Gigabyte Mobo, because I did have S3 sleep problems with that, and was as frustrated as you are now! Also, AMD and ATI are one and the same, and the Asus was an AMD accredited/approved socket AM2 Mobo, so I was fairly sure it would all work together, and it does.
I've got all the latest drivers, but it's worth saying that with standard 'Windows update' audio driver sometimes I'd have problems with either no-sound or distorted sound after wake-up, but with the latest RealTek driver from their website there are no such problems. With very early Catalyst drivers there were also problems with the screen not coming on after wake, but they've all been long-since fixed by ATI.
I guess if there are 'bugs' in the Vista S3 sleep process, then it's in the way it allows drivers to 'break the rules', or at least not do things Microsoft were expecting them to do - otherwise I can't see how everybody's experience is so different.
I wish there was single point of reference for 'Green-Button-User accredited' hardware and drivers, where everyone can rely on it working in the real World, and not just on the manufacturer's say-so.
JB