When using RAM Doubler, do not increase the memory allocation of your applications unless you are experiencing “Out of Memory” errors. Some programs (for example, Adobe Photoshop) have their own virtual memory system which is optimized for those applications.
NOTE: RAM Doubler is not currently compatible with the Radius Rocket or Fusion Data System’s TokaMac accelerators. Other products which disable themselves under non-unity memory-mapping environments (like virtual memory or RAM Doubler) are also not currently supported.
NOTE: RAM Doubler is not currently compatible with the FWB SCSI JackHammer. If you use the JackHammer, your startup hard drive must be connected to the standard SCSI bus, not the JackHammer.
NOTE: RAM Doubler can not fully double a Macintosh with more than 128 MB of RAM. Under this case, RAM Doubler will only extend memory up to 256 MB.
NOTE: Some hard drives, notably early versions of Alysis’ eDisk, allocate memory in a way which prevents RAM Doubler from extending RAM. Contact your hard drive vendor if you receive the alert concerning a driver not in the system heap.
NOTE: If you use Apple's RAM Disk, the memory for the RAM Disk is allocated by the Macintosh ROM and is thus unavailable for doubling. Therefore an 8 MB Macintosh with a 4MB RAM Disk will only have 8 MB of available RAM, not 12. Also, to protect against performance loss, the amount of your physical RAM, minus the size of your RAM Disk, should never be less than 4 MB.
If you see the message that RAM Doubler may not fully double RAM:
RAM Doubler may not fully double your memory if your Mac is using 24-bit addressing and you have more than 5 MB of physical RAM. This is because 24-bit addressing can only manage a total of 16 MB of memory, of which some is used up by hardware (serial ports, floppy drive, ROMs, and video, network or other NuBus cards). You can still work in 24-bit addressing; however, you will not be able to use as much additional RAM as if you had switched to 32-bit addressing.
Before switching to 32-bit addressing, you should check that all your programs, including applications, system extensions (of any kind), NuBus cards, and hard disk drivers are compatible with 32-bit addressing. If you do not check, you may run into unexpected difficulties with your computer, not because of RAM Doubler but because of enabling 32-bit addressing.
If you have trouble restarting your Mac with 32-bit addressing on, restart your Mac and hold down the Shift key to disable all extensions. Next, remove all non-Apple software from the System Folder, and Extensions and Control Panels folders. Then, place one extension into the System Folder and restart. Repeat this process and eventually you should find the extension that is not compatible with 32-bit addressing. You should contact the manufacturer for a compatible version.
