Apple Performa 250 Memory

Main Memory
Maximum Memory - 10 MB
Memory Slots - 2 (1 bank of 2) install in pairs

Video memory
Maximum Memory - 768 KB
Memory Slots - 1

M1310LL/A (256KB Apple Mac Video Memory Upgrade) $2.78

M1311LL/A (512KB Apple Mac Video RAM Memory Upgrade) $4.98

APPLE-1MB-SIMM (1MB Apple Mac 30-Pin non-Parity SIMM) $0.88

APPLE-4MB-30PIN (4MB Apple Mac 30-pin non-Parity SIMM) $3.78