This is hard to answer as there were quite a few models released with many revisions made to the motherboards.
Chip memory = Used by the custom chips as well as the processor (eg: graphics/sound). Custom chips can't access fast memory directly - only 'chip' memory.
(SLOW/FAKE) Fast Memory = What many of the trapdoor 512k expansions provided. Used the same access method as chip memory therfore it was just as slow as chip memory. Some of these cards enabled them to be used as an extra 512k of chip memory bringing chip memory to 1Meg.
(REAL) Fast Memory = Only the processor has access to this memory and it does not have to wait in the queue to access it along with the custom chips (ie: it is faster).
For game playing the basic configurations would be...
Amiga 500 MC68000 7mhz
Kickstart 1.2 ROM
512k chip memory
512k (FAKE/SLOW) fast memory
Amiga 1200 MC68020 14mhz
Kickstart 3.0 ROM
2 Meg chip memory
* 4 meg (REAL) fast memory (although the standard 1200 only had 2 Meg chip some of the later games required more memory)
I had a Kickstart 1.2 A500 1/2 meg chip 1/2 meg fast for years and recall no problems running non-AGA games with only exceptions being games like STARDUST which required the 1/2 meg fake fast memory to be set as chip memory to give a full 1 megabyte chip memory.