Is My DVD-RW Dying ?

[vxdesigns]

Hi long time no see people how are ya'll
I was hoping i get an opinion from my fellas before i went ahead and screamed at Dell.
If anyone remembers about the time when i posted about purchasing a Dell Inspiron 6400 laptop ? Well this issue is related to that laptop.
Everything has been running smooth so far until recently i ran into issues. I have burned about 50-100 cds and dvds altogether without any issues but since a few days whenever i burn something i am getting errors at like 80% done status or even 90% done status and it's very frustrating. Although the status window of nero shows 8x speed but it takes like 10 mins to burn a 300 mb file which wasnt the case before. So i think somethings wrong with my DVD-RW drive or mayb it's these new DVD-R's which i bought recently from a warehouse which had a massive sale. I got 100 dvd-r's for like $11 canadian and i was so happy until now.
So my questions are as follows

1) what would you do to find out if your dvd-rw drive is dying ?

2) what would you do to find out if it's your dvd-rw drive or your blank dvds which are corrupt

Thx for all the help in advance

[GX1_Man]

Try a new DVD from a major manufacturer.

This problem started AFTER you began using the "el cheapos"? If so, that sounds like cause and effect and nothing to do with Dell.

If that doesn't reveal the issue we'll explore the other possibility, but if you see hoofprints it makes more sense to start looking for horses rather than zebras.