What firmware does my AD-500W have?

Like the AD-600A DVD player, the 500W now has different firmware. Any 500W players bought before mid-April 2001 will most probably have APE-500W-2 firmware as shown by this picture of the main board:

However any Apex 500W player purchased after mid-April 2001 will most likely have newer firmware called "APE-500W-3". The only way to check which version of firmware you have is to open up the player and inspect the sticker on the firmware chip.

I get email all the time asking if a player with APE-500W-2 or APE-500W-3 can be upgraded to APE-500W-4. The answer is YES! All three versions are interchangeable.

I have received a comparison between APE-500W-3 and APE-500W-4 firmware:

"I bought two AD-500W and also have a friend who bought one (North America). All threre are W-3 firmware. Had trouble with all three skipping while playing The Matrix in certain scenes. You had to watch very carefully but it would skip on occassion. I figured that maybe the firmware revision was to address this problem so I decided to exchange them for the W-4 version. I am now currently testing two of them and so far no skipping whatsoever. I also noticed a change in the setup menu compared to the W-3. In the W-3 I believe there was only two language choices in some of the menus ( English and Chinese ) in the W-4 there is now also Spanish, German and French. Anyways I thought I would share this info."

Thanks for that! Much appreciated. If anyone does find any more differences please email me!