5 upvotes, 1 direct replies (showing 1)
View submission: I'm still struggling understanding RAM types/upgrades for OCS 500.
The A500 has 3 main ways it can be upgraded.
1 the trap door slot that can be used to upgrade from 512k to 1MB of ram for all A500 models or from 1MB of ram to 2MB of ram for the A500+.
All A500 shipped with 512k chip ram that can be accessed my both the CPU and the chipset. With the trapdoor exanpansion slot being designed to allow you to double the ram by adding another 512k of ram. Which shows up as fast ram and which can only be accessed by the CPU but as the chipset cant access it directly it cant be used for graphics or sound directly just storing program data.
The sidecar expansion slot was designed to allow you to add an external harddisk, larger 8MB ram expansion and or a CPU upgrade.
Finally its also possible to fix internal expansions that sit between the sockets for the chips such as the CPU or other custom chips as they are socketed to upgrade things like adding modern HDMI out, or an internet RAM and Hd controller.
If you are just going to use your amiga to play games from a floppy drive or gotek drive 99% of the time all you need is the 512K trapdoor ram expansion to give you one 1MB of total system ram.
Now in resent years there have been a few games released that need 1MB of chip ram like the A500+ and A600 had as standard or to allow WHDload to let you play games from HD with workbench is using some of the ram.
Most A500 can be modded to turn the 512K in trapdoor slot to into another 512K of chip ram to give 1MB like the A500+ and A600 shipped with. But that request making some modifications to the motherboard and a newer revision of one of the custom chips. Most A500 with green power lights shipped with the right chip to do this but not all of them.
So before planning to do the 1MB chip ram upgrade you need to either use the Program SysInfo to check if you have a 1MB Angus chip, which can be downloaded from ambient if I remember correctly or open up the amiga and check the custom chip versions and your A500 motherboard revision.
Comment by spacemidget75 at 01/03/2025 at 17:57 UTC
2 upvotes, 0 direct replies
Thank you! Yes I was looking at either a PiStorm and WHDLoad or AGS on a CF card (which I believe requires 1 MB chip and 4 Mb fast.