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I think all DVD drives can read DL disks but only DL drives can burn DL disks.

The very earliest DVD drives have difficulties with written DVD DL discs, but handled pressed (aka: factory) DVD DL discs.

Also, the earliest DVD drives, when they could handle dual-layer at all, generally could only handle DVD-R DL discs, not DVD+R DL discs. (For Apple devices, it is safest to use DVD-R, not DVD+R.)
 
Spent way too much on my cube although love it. It has hard to find the 1.8ghz cpu

Has an SSD as well as a GeForce 6200 now
 
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