With the rear of the computer away from you, you will see 4 SIMM sockets on the right side of the motherboard. The front two sockets are for RAM; the rear two for VRAM.
Each RAM socket can be filled with a 4 MB, 8 MB, 16 MB, or 32 MB SIMM – they need not be of the same capacity. (There is no support for 1 MB, 2 MB, or 64 MB SIMMs.) The 72-pin SIMMs must be 80ns or faster.
If you install two SIMMs, they should match in speed or you may have memory problems. If you match the speed and capacity of both SIMMs, the 610 will use memory interleaving, which can be 5-10% faster.
VRAM, Where More Memory Means Less Speed
The 610 ships with 512 KB VRAM on the motherboard. You can upgrade this to 1 MB by installing two 256 KB VRAM SIMMs in the VRAM sockets beneath the floppy drive.
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