It would have been a lot easier to tell the difference between the two had you specified the sSpec or processor # of the CPU so if you could post the exact processor number/sSpec number so that we can tell you the exact difference between the two. However here's a brief, all Core2Quad processors of 2.83GHz (SLB8V, SLGAE, SLAWQ)are based on 45nm manufacturing technology with 12MB cache, 1333MHz FSB and 4 cores each which definitely makes it better in performance and low voltage utilization saving you a lot on electricity bill. While Core2Duo desktop processor of 3GHz (SLA9U, SLB9J, SLAPL) come with 2 processing cores, one of the three is based on 65nm manufacturing technology with 4MB cache while the rest of the two are 45nm based with 6MB cache, FSB of all three in this case is the same as Core2Quad i.e. 1333MHz.
Core2Quad in this regard is definitely better due to more processing cores, greater L2 cache and 45nm manufacturing technology consuming lesser electricity as compared to Core2Duo.
If you could kindly state the exact processor number and it will make it a lot easier for us to give you the exact difference and suggestion lest you require that.
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