DMX Auction Expected to Net Thousands, but Ex-Wife Wants Kids to Get a Cut

6:57 PM PT -- The adminstrators of DMX's estate tell TMZ ... "We were surprised and disappointed to learn of this auction, which is not authorized and was not cleared by the Estate of Earl “DMX” Simmons."

They continue ... "The Estate holds rights in the recordings and written materials being offered for sale — including significant intellectual property rights — all of which we will fiercely protect. We consider this a violation of the Estate’s rights and will be pursuing appropriate action."

DMX's memory will live on thanks to an upcoming auction ... GottaHaveRockandRoll is unleashing a one-stop shut'em down, open-up shop full of the late Ruff Ryders rapper's earliest moments en route to becoming a hip-hop legend!!!

The treasure trove of DMX goodies features over 30 mind-blowing lots of rap relics and focuses on his rise to fame between 1992-1994 ... and is expected to fetch $20,000-$40,000!!!

GottaHaveRockandRoll President Dylan Kosinski tells TMZ Hip Hop that one of DMX's earliest close music industry pals provided the artifacts to the auction house ... there's even a poster when he opened for Wu-Tang Clan in 1994!!!

The revelation is troubling for DMX’s first wife, Tashera Simmons, who tells us… "The seller is not a family member to our knowledge, the auction is disheartening and insensitive as these precious items should go to Earl’s children."

The cassettes are being sold as artifacts ... same with the VHS tapes. He recorded everything himself, took the footage himself, owned all the equipment, and will get the proceeds from the auction.

X became a massive success in 1998 -- making history by releasing 2 albums to hit No. 1 on the Billboard 200 in the same year ... and the collection boasts hours of unreleased music that shows how he honed his skills.

There are 4 separate cassettes filled with unheard gems such as freestyles and diss tracks and each tape is estimated to sell for more than $10,000.

Handwritten lyrics from DMX's 1993 debut single "Born Loser," a music video of an unreleased track, early in-studio sessions, and concert posters are also included.

The lyrics rattle off some of his hip-hop influences at the time ... N.W.A, Ice-T, Queen Latifah, Ice Cube, Naughty By Nature ... years before he would become their artistic equal.

Still, Tashera tells us the family understands the zeal for anything X created ... he was a soulful genius.