Holy cow, fellow spuds, the world may be coming to an end - CBS finished first in the ratings last week.

Well, the Big Eye's win isn't quite that shocking, but it is a big surprise nonetheless. CBS hadn't won the first week of a season since 1984, and it hadn't won any week since January 1987.It wasn't an overwhelming victory - CBS averaged a 13.6 rating, second-place NBC a 13.4 and third place ABC a 13.2. (Each ratings point equals 931,000 homes.) That's the closest premiere week since 1966.

But for the perennial cellar dweller, it was a much-needed boost.

CBS showed surprising strength on Monday night - "Designing Women" tied for third, "Murphy Brown" was sixth, "Major Dad" was 10th and the new drama "The Trials of Rosie O'Neill" was 28th - the highest rating of any new show in its regular time slot.

Not only that, but "Murder She Wrote" beat ABC's "America's Funniest Home Videos" for the first time on Sunday night, perhaps indicating that "AFHV" is burning out even faster than expected.

On the other hand, perennial champ NBC is having a bit of difficulty dealing with anything but success. "Premiere week almost by definition is an atypical week," the Peacock's press release began.

Funny, NBC never said anything about "atypical" premiere weeks when the network was winning them.

And there are definite signs of trouble for the Peacock. CBS' ratings were up 5 percent over the first week of last season, ABC's up 1 percent - and NBC's down 20 percent.

Not only that, but NBC was counting on its crop of new series to lift the network into a "new age of dominance," according to Entertainment Chairman Brandon Tartikoff. But none of them took off - "American Dreamer" finished 20th, but that was for a special showing after No. 1 "Cheers." In its regular time slot, "Dreamer" plummeted to 52nd.

And NBC's greatest hope, "Fresh Prince of Bel Air," could only manage a tie for 40th - and it finished behind CBS' awful "Uncle Buck."

But as bad as things were for NBC, they were much, much worse for Fox. "The Simpsons," although still in reruns, got killed by "Cosby." As a matter of fact, "The Simpsons" finished fourth in its time slot, behind "Cosby," "The Flash," and "Father Dowling Mysteries."

Fox's highest-rated show was No. 45 "Married . . . With Children." And the fourth network occupied the bottom 12 rungs on the Nielsen ladder.

Ay, caramba. Fox must be having a cow.NIELSEN LIST: We're not going to make a habit of this (who wants to read this entire list very often?) but here's the complete list of Nielsen rankings for the first week of the 1990-91 season. (New shows are in italics.) We'll check back at the middle and end of the season.

1. "Cheers," NBC; 2. "Roseanne," ABC; 3. (tie) "60 Minutes" and "Designing Women," CBS; 5. "The Cosby Show," NBC; 6. "Murphy Brown," CBS; 7. "Golden Girls," NBC; 8. "A Different World," NBC; 9. "Empty Nest," NBC; 10. (tie) "Unsolved Mysteries," NBC, and "Major Dad," CBS; 12. "Doogie Howser, M.D.," ABC; 13. "Murder, She Wrote," CBS; 14. "Growing Pains," ABC; 15. "In The Heat of the Night," NBC; 16. "Who's the Boss?" ABC; 17. (tie) "Field of Dreams" - "CBS Tuesday Movie" and "Matlock," NBC; 19. "Wonder Years," ABC; 20. (tie) "American Dreamer Preview," NBC, and "Married People Special," ABC.

22. "NFL Monday Night Football," ABC; 23. "Head of the Class," ABC; 24. "Leona Helmsley: The Queen of Mean" - "CBS Sunday Movie"; 25. "Knots Landing," CBS; 26. "America's Funniest Home Videos," ABC; 27. "Family Matters," ABC; 28. "Trials Rosie O'Neill," CBS; 29. "She Said No" - "NBC Sunday Movie"; 30. "Full House," ABC; 31. "Jake and the Fatman," CBS; 32. "Married People," ABC; 32. "America's Funniest People," ABC; 34. "Flash," CBS; 35. "Uncle Buck," CBS; 36. "Rescue: 911," CBS; 37. "Carol & Company," NBC; 38. "Babies" - "NBC Monday Movie"; 39. "Beverly Hills Cop" - "ABC Movie Special"; 40. (tie) "Going Places," ABC, "20-20," ABC, "Hunter," NBC, "Fresh Prince of Bel Air," NBC.

44. "Evening Shade," CBS; 45. "Married . . . With Children," Fox; 46. (tie) "An Evening With . . .," ABC, and "The Running Man" - "ABC Sunday Movie"; 48. "World's Oldest Living Bridesmaid" - "CBS Friday Movie"; 49. "Tribute to Oprah Winfrey," ABC; 50. "Macgyver," ABC, and "Fanelli Boys," NBC; 52. "American Dreamer," NBC; 52. "Law and Order," NBC; 54. "Dear John," NBC; 55. "Top Cops," NBC; 56. "Ferris Bueller," NBC; 57. "Working It Out," NBC, and "Father Dowling Mysteries," ABC; 59. "Murder C.O.D." - "NBC Friday Movie," and "In Living Color," Fox.

61. "Gabriel's Fire," ABC; 62. "Young Riders," ABC; 63. "Get A Life," ABC; 64. "Primetime Live," ABC; 65. "Life Goes On," ABC; 66. "Parenthood," NBC; 67. (tie) "Hogan Family," CBS, "Camp Cucamonga" - "NBC Sunday Movie" and "Simpsons," Fox; 70. "Family Man," CBS; 71. (tie) "48 Hours," CBS, "Lenny," CBS, and "Doctor, Doctor," CBS; 74. "Super Bloopers-Practical Jokes," NBC; 75. "Babes," Fox; 76. "E.A.R.T.H. Force," CBS; 77. "Parker Lewis," Fox; 78. "America's Most Wanted," Fox; 79. "True Colors," Fox; 80. "Cops," Fox; 81. "Totally Hidden Video," Fox; 82. "Haywire," Fox; 83. "Against The Law," Fox; 84. (tie) "DEA," Fox, and "21 Jump Street," Fox; 86. "Glory Days," Fox; 87. "Alien Nation," Fox; 88. "American Chronicles," Fox.