I am Not a Geek dot com has posted a review on the Samsung SW-216

While you may have a 52x CD-ROM, the rating of 52X is a maximum rating, and on the inside tracks of the CD where the CD-ROM starts reading from, you are only going to get about 16x at the most. CD Recorders speeds are based on a CLV rating not a CAV rating like the most CD-ROMs past 8x, which means they burn at the same speed throughout the CD. So your 24x burner will actually start burning at 24x while your 52X CD-ROM is only starting to read at 16X, which will cause a buffer underrun error, but more likely your 24x burner has BURN Proof or Just Link enabled and your burner temporarily stops and waits for the CD-ROM to catch up and then resumes the burn, slowing the overall process.

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