“Transformers” has rocketed past the competish to become the fastest selling DVD of the year.

Paramount Home Entertainment sold more than 8.3 million “Transformers” discs its first week on shelves to outpace “Happy Feet,” “300” and “Night at the Museum” during their debut weeks. Tally includes discs sold to consumers and rental stores in North America.

“Happy Feet” is the year’s top seller to date, having sold around 10 million discs since its March 27 debut, according to studio estimates. “300” is next up with sales north of 7 million units, followed by “Night at the Museum” and “The Departed.”

“Transformers” also sold well on hi-def despite director Michael Bay’s concerns about Par’s decision to back HD DVD format only. Studio said it sold more than 190,000 HD DVDs of the pic during its first week for one of the best hi-def bows yet.

Warner Home Video sold more than 250,000 hi-def copies of “300,” for example, but that was on both HD DVD and Blu-ray combined. With Par’s decision to back HD DVD only, Warners is the only studio to back both hi-def formats.

Studio said it sold more than 4.5 million “Transformers” discs on Oct. 16, the first day it hit shelves.

Boffo DVD bow follows a record setting theatrical debut this summer. “Transformers” has grossed more than $700 million at the worldwide B.O. The studio is fast-tracking a sequel for the pic.