i recntly bought a used dell 370 workstation it cam with 2, 512 ram chips (samsung 512mb 2rx8 pc2-3200u-333-10-b1)and ordered online 2 ,1 gb ramchips that came and say pc2-5300 ddr2 sdram 128x64 and below are the computers specs i was wondering if i can use both the new and old chips together causee i have 4 spaces for memory but the specs say dont mix ecc with non ecc and something else about sdram i am lost dont know what the diference is or if what either  chips are if there ecc of not they dont say please help i have a dell precision 370 with pentium 4 ht 3.6 gh processor