soundcard response to too-high bit depth settings

I’ve been recording onto my iMac G4 with Audacity set to 32-bit float, but just today had the bright idea to check System Profiler for the soundcard specifications for bit depth. Here’s the relevant part of what it says about my soundcard (Burr Brown PCM3052):

Formats:
PCM 16:
  Bit Depth:    16
  Bit Width:    16
  Channels:     2
  Mixable:      Yes
  Sample Rates: 32 KHz, 44.1 KHz, [etc...]

PCM 24:
  Bit Depth:    24
  Bit Width:    32
  Channels:     2
  Mixable:      Yes
  Sample Rates: 32 KHz, 44.1 KHz, [etc...]

So no 32-bit float format. Is there an easy way to guess what it’s been doing with my requests to record in 32-bit float? Or do I need people with knowledge of this specific soundcard?

The recorded data will, if necessary, be resampled to the format that you have selected. I think that this is normally handled by the sound card driver rather than by Audacity. Resampling to a higher bit depth will not improve (or reduce) the sound quality, but will allow editing and processing to be done more accurately.