Normally I would say no problem. But sometimes RAM of different breeds can cause conflicts hardware wise. Its safest to use all the RAM of the same kind, spec, speed, etc. If you do you use two different speed RAM then the slower speed is what will be used. From my experience only PC2700 DDR333 RAM is what desired in a MDD Dual 1.25 G4. I never tried to put PC3200 in mine so I cannot faithfully tell you what would happen. EVEN Weirder for me is I got 4 sticks of PC2700 DDR333 SDRAM all from the Same Company. I bought the first Two about a year later than the other Two. and in my System Profiler it stated the First two were PC2600U and the other two as PC2700. That I never figured out. Good Luck, Luke Rademacher Liquid Zone Graphics Mac mini 2.0Ghz Intel Core 2 Duo, 3GB RAM, 80GB HD, Combo DVD/CDRW, Mac OSX Leopard 10.5.5, ext NewerTech miniStack w/ 320GB HD. MDD Dual 1.25Ghz G4, 2GB RAM, 250GB/120GB/80GB HD's, 16x DL DVD±R/RW Superdrive, Mac OSX Tiger 10.4.11, Classic Mac OS 9.2.2. External 1TB HD FireWire 400 Intel Celeron 2GHz, 1GB RAM, 80GB HD, Ubuntu Linux 8.04 5.5th gen 80GB Enhanced Video iPod Canon CanoScan 8400F Canon Pixma iP4500 On Jan 15, 2009, at 1:53 PM, Dan A. Currie wrote: > Hello All, > > Can you mix PC2600U-25330 DDR Ram with PC3200 DDR Ram on an MDD > 1.25 dualie? > > THX, > > Dan Currie > > > _______________________________________________ > G4 mailing list > G4 at listserver.themacintoshguy.com > http://listserver.themacintoshguy.com/mailman/listinfo/g4