PX-716A vs. PX-716UF: 100 EUR difference justified?

I recently bought a PX-716A which is simply the internal IDE version of the PX-716UF. Since I want to use it in a flexible way, I also purchased an IDE/USB2.0 Adaptor (e.g. this one: USB 2.0 zu IDE Adapter Kabel - HDD Konverter 2in1 [Disclaimer: I don’t want to advertise this product here; just as info!]) and it definitely rocks :clap: ! The drive is recognized by Plextools as an PX-716UF, even the firmware update works with this connector, and the Read/Write-Speed is not limited at all. The beneftit: PX-716A costs ~115€ plus the adaptor ~10€, this is dramatically cheaper than the external version which costs about 215€. Is this high prize for the -UF justified?!

The USB2.0 and Firewire chipests used in the 716UF case are guaranteed to support full 16x DVD transfer rates, whereas often other enclosures have chipsets that for whatever reason will not, though yours does obviously. The only other reason really is for plextor support of the external drive, and the fact that the 716UF case looks so cool :stuck_out_tongue:


I recently bought a PX-716A which is simply the internal version of the PX-716UF (external, USB). The price of the PX-716A is somewhere around 115 EUR, and the price of the -UF is around 215 EUR. Since I need the flexibility of the external drive, I just purchased a simple USB 2.0 to IDE adaptor cable [Disclaimer: I don’t want to advertise here, just as info], for only ~10 EUR. I just use the drive without a case. With this adaptor, the 716A is recognized by Plextools as an PX-716UF, and even the firmware upgrade was no problem! The read/write transfer rate is not chopped at any lower speed since I successfully made a test at 16x speed for a DVD. The only disadvantage for me seems to be the ‘experimental setup’-like connection of the drive with the computer. On the other hand, I always have the option to use the same USB/IDE-adaptor for easily plugging in other devices (as e.g. the hard disk of my sattelite receiver). It really rocks!
Now I’m asking myself if there is any other disadvantage of this setup. Is there any feature with the PX-716UF that is not with the PX-716A? Is the high price of the PX-716UF really justified?


you’ve started an almost identical thread one hour ago… :confused:
Isn’t it better to continue on the other thread? :slight_smile:



oh, I’m really sorry. It’s true. When I wrote the first thread and pressed [Submit], my IE aborted with an error and thought I’ve lost everything I’ve written so I did it again…
Can we just erase this one or close it?

I am not a moderator in this subforum, so I can’t do it.
But I’m sure that G@M3FR3@K or some other mod will merge the two threads soon, so no problem. :wink:



Merged the two threads :wink:

About your question; if you’re not experiencing any problems using an unofficial enclosure then I see no reason why you should pay 100 Euro’s extra for the official PX-716UF. But, I’ve seen reports about people using the PX-716A in an unofficial external enclosure and who were experiencing problems.

I had the same thing myself. Because I have a barebone computer I only have room for one internal optical drive. So, I decided to use my PX-716A in an unofficial Plextor external enclosure that was previously used for a PX-W4824TU burner. The drive would work fine but I was not able reach any read or write speed over 10X or so. When I got a real PX-716UF drive all was fine and 16X was not a problem.

Thanks for merging the two threads…

In fact I must admit that I’ve had the reported problem myself before I got the USB<->IDE adaptor I mentioned above. While I was waiting for the ‘eBay’ paket when I temporarily used another controller that is attached to a cheap ‘external usb harddisk enclosure’. Though this enclosure promises to provide the full speed of USB2.0, I only reached a DVD read transfer rate equal to 4.8x speed!
Probably the IDE controller of this enclosure does not support the IDE PIO Mode 4, which is relevant for DVD unit?!

External drives have nothing to do with DMA, this only applies to internal units. There is a converter in the external enclosure though that converts the USB or FireWire to IDE so you can use any ATAPI/IDE device in it.

Yes, but I did not speak about DMA. PIO modes do not use DMA. I found the following list in the net:

PIO Mode …Cycle Time…Maximum Transfer Rate (MB/s)
Mode 0 … 600 … 3.3
Mode 1 … 383 … 5.2
Mode 2 … 240 … 8.3
Mode 3 … 180 … 11.1
Mode 4 … 120 … 16.7

Modes 3 & 4 are classified as ATA-2, below is ATA. If an IDE controller only supports the ATA-Modes, it will provide a max. of 8.3 MB/s. This is enough for 52x CD, but not for 16x DVD.
Or something like this.
This is just what I’m thinking. Not sure…

Kacki, this is interesting. I was also thinking to buy an USB2.0 - IDE adapter instead of external enclosure. Can you please post some screenshot for us just to see if your PX-716A in the adapter can still perform 16x writing:

  • Nero CD Speed create data disk with PowerRec off, use 16x media. Wanted to see if it can reach 16x. Sorry you’re going to waste a disk.
  • Nero CD Speed burst rate, just the number, no need for screenshot.


I’m just wondering 'cos in my last answer I found out that PIO Mode 4 “only” supports 16.7MB/s. However, 16x DVD correxponds to 22.160KB/s according to Plextor’s specifications. Hmmmmm… I definitely have to check it again. So far I only used PLEXTOOL’s Read Transfer Rate Test with a ‘stamped’ DVD-ROM that was filled up to a level where a max. ~14x rate was reached.

So, Nero Speed Disk provides a function to create a FULL data DVD in order to reach 16x speed in the outer region? I hope I can find some 16x media…

Ok, I did it, or better: I tried. Since I had no 16x media, I took the 8x certified EMTEC disc (manufactured by CMC). I once made a FE/TE-test with this media and it told me that it could be burned at maximum speed. I thought this would mean it works with 16x. So it began to burn at 6x and after approx. 30 sec, the speed did not even reach 7x, it was a coaster :sad: ‘Seeking error’ or somewhat like that. F*ck.

Then I performed the Speed Test with Nero. I got the Burst Rate 27MB/s as a result (see attached screenshot). Unfortunately, I did not manage to perform any speed test that starts with 6x speed! I tried several DVD-ROMs, all of them started at 5x, resulting in max. 12x at the end, though ‘Enable SpeedRead’ is ticked and ‘DVD Read Speed’ is set to ‘6-16x’.

How reliable is the Nero test? Is the value 27MB/s for the burst rate a realistic one? That would mean, the IDE controller itself provides a DMA mode in its IDE part…

Max speed for CMC MAG 8x discs is 8x. All of your DVD-ROMS were dual layer; the max read speed for these is 12x. To get a full 16x read, you need a single layer pressed DVD-ROM.

first screenshot: Intenso media (16x certified). red = with PoweRec, green: w/o PoweRec
second screenshot: Verbatim media (16x certified). red = with PoweRec, green: w/o PoweRec

All tests were Write Transfer Tests by PlexTools in simulation mode.

The two discs have been tested with the FE/TE-Test before; BOTH discs FAILED the test (“Disc should not be written at maximum speed”).

Kacki, thanks for the time and effort for testing 16x media. I think the USB2 - IDE adapter is not up to the speed. From your scans look like the drive can’t reach 16x.

Hmm… Zevia, perhaps you can answer me some questions in this context:
do you think 16x is not possible because there is a buckle in the graphs at ~ 15,5x speed? Could this also come from the media?
If the adaptor limits the speed here, burning at 12x would be safe though? What would happen if I burn at 16x? Would I get a buffer underrun at the end of the disc? If BurnProof jumps in at ~15,5x, would I get any problems with readability of the disc?
I will try to repeat the same test with the CMC 8x, these media did at least pass the FE/TE test at maximum speed…
What about the “bust rate” of 27MB/s Nero Speed Disk showed me?

Yes, you can clearly see the irregular pattern at the end of the graph. If it was a media problem the graph wouldn’t be as irregular but would rather show one or two speed drops, lowering the write speed to a fixed 12X, 8X or even 4X.

Yes 12X should be possible and if you were to burn at 16X you would indeed get a buffer underrun but since the Plextor (or any other DVD burner) can pause the write process, this is not a problem really. It just results in a slower write performance than a real 16X burn. It shouldn’t cause readability problems.

This is lower than you would see from a PX-716A running in UDMA mode 4 (around 45MB/s burst rate).