Enclosure causing burn slowdowns at ~14x?



I have a Lite-On DH20A4H, stock QP5A firmware, in a Plumax PM-525U2-PCS USB enclosure. I use TYG03 discs. Using DiscSpeed to create a 16x disc, I’ve noticed my burns move steadily upward in speed, until it hits about 14x, when drive speed nosedives, and the drive finishes the disc out at usually at 8x.

My sneaking suspicion is that the enclosure is causing the slowdown. Unfortunately, I only have a laptop, so mounting the drive directly to an ATA channel isn’t possible. I do have an Oxford 911 based enclsoure that I could dig up, but my past experience with that enclosure has shown that it tops out at 8x maximum.

Can anyone take a look at my scans and see if I’m on the right track with the enclosure being at fault for my mediocre speeds?

Other, related questions:

  • I think this enclosure is a Cypress chipset, but some info on the net suggests it’s a Prolific. Is there a way to determine the chipset, and possibly the firmware version on the chipset?
  • Would it be worth my time to test newer firmwares for my drive?
  • Should I just accept this and just burn at 12x or 8x?



I’m too lazy to google to see if your Plumax enclosure uses a Prolific PL-3507, but if it does, it’s normal that it won’t reach 16x during writing.


I just plunked around a bit in device manager and found that it’s indeed a Cypress AT2LP RC7 v2.4.

After perusing the gigantic external enclosure threads, it appears that 12x is pretty feasible on AT2+ enclosures like mine, while Ox911 tops out at 8x, but Ox911+ can reach 16x.

I may just sit tight with this setup for a little while longer, and move to an eSATA setup in a few months if I really want some extra speed (and new toys).