I'm board, board, board.
We got this expansion board for our 4000/040, it's from DKB and will also fit the Amiga 2000 and 3000. The Rapid fire features two simm sockets that take standard 72 pin simms, its onboard SCSI controller allows you to add full array SCSI devices, including CD-ROM drives, hard disks, scanners, etc. The Rapid fire is a hard card allowing you to mount a 3.5" hard disk directly to the board.
The simm configurations can be two 2mbs, two 4mbs, or one 2mbs and one 4mbs, but up to 8 megabyte only, this is to ensure compatibility with the 2000.
The board has a handy table printed on the board itself showing how to configure the three jumpers for any combination of simm modules. Reading the manual tells you all you need to know, but if stuck there is a technical support line number.
Installed is a Segate 1Gig medalist ultra slim hard drive to the board, also a Toshiba quad speed SCSI CD-ROM drive. To do this all I needed was a home made extra long 50 pin SCSI ribbon cable, as the one supplied is short and with only two sockets, this is fine for adding one device.
The 4000 has the revision 9 buster chip (buggy), but the board still handles data fast and with no errors. I have not yet installed any memory to the board, whether this will make the buster show its bugs I am not sure I will let you know. The price of the board is £139.95, wow quite steep I hear you say, well yes maybe a little, but be careful as some others are not being made any more and some do not take simms, but drams, which after paying £99 for a SCSI board then buying drams could soon bring it up to a similar price.
I rated it 88% because of price. Any memory problems are due to the buster chip in the Amiga 4000, you will need the revision 11 buster to overcome this, which I've been quoted £78 to replace, that includes postage. Shit, something else to get!