4x dvd-r burn only under 2x

way? i used TYG02, SONY DRU-510A

Are you sure this is genuine Taiyo Yuden media? See this thread for information on how to determine whether or not your TYG02s are real.

Your discs could be fakes that are missing 4x write descriptors.

If you’re sure your media is genuine, then I’m betting the problem is your drive’s firmware. Your drive is from 2003, before TYG02 media even existed. If you still have older firmware, then it’s not going to recognize TYG02 media as being valid 4x media (and 2x burns will likely be using a default strategy instead of one tailored to Taiyo Yuden discs). Download the latest Sony firmware (v1.1a) here and give it a shot.

Yup, if it isn’t fake then it is definitely a firmware issue and your drive needs an update.

TYG02 is not even 4X rated media but 8X rated media…

A good start would be to mention the brand and origin of these. Also you burner looks quite old so it’s probably not a media issue.

I got 25 pack TYG02 from Office Depot there are TWO codes:307T, IFPI FW05

You mean they are unbranded? Don’t know about these codes, are they form the merchant?

Look at the inner hub, you should find a serial starting with “GG” or “TG” on genuine TYG02 discs. Follow the link reptile gave above, see second post in the thread (by Wesociety).