I got 2 512 SSD in a Raid 0 in mine (A1342) and I found 10.13 really runs the best. Mojave was ok but a tad slow with the C2D.Already dropped versions my hardware cannot handle - 10.0 to 10.3. My macbook A1342 can run from SnowLeo up to High Sierra. Quad can use only 2 (4 if we count servers), so line is from 10.4PPC up to Catalina (may be I'll try to look what OpenCore can do with A1342)
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