slippymadfrog : this is what I found on The Big Book :
GVP Impact Series II 4000 HC+8
The main differences between this version and the 2000 HC+8 seems to the SCSI chipset used. The original card uses a western digital chipset whereas this card uses a DPRC chipset. The card also has 8 x 30pin SIMM slots for adding up to 8MB of additional RAM. The card can use either 1MB or 4MB 30pin SIMMs, however the maximum RAM you can add is still 8MB, even with 4MB SIMMs.
Is this enough as an answer ?? It's all I found ...