We already wrote that 65 nanometre RV630 core has some issues but luckily A14 fixed this issue. A13 chips had issues with HDMI over DVI part as it simply didn’t work as it should.
The new revision of the chip is about to fix this issue and the Radeon HD 2600XT and PR cards based on RV630 are about to start shipping late June to middle of July.
All in all things will be fine but, ATI suffered quite a big slam in its face with this serious issue. RV610 was also affected by the same bug.
So obviously something went wrong with UVD part. We reported about this delay back in late March here.