There’s been a change in the way auds are watching scripted drama on television this summer, with the Nielsen gap between broadcast repeats and cable originals closing.

Ratings for heavyweight dramas ranging from “CSI” and its spinoffs on CBS to “Grey’s Anatomy” on ABC, and even the hot “House” on Fox are down by about 15% vs. last year at this time as the Big Four are relying more and more on reality shows to generate the bulk of their ever-dwindling summer audience.

The top drama repeat on the broadcast nets last week — CBS vet “CSI” on Thursday — ranked 17th among all programs in adults 18-49 (2.5 rating/8 share). The slots above “CSI” in the weekly rankings were occupied mostly by firstrun reality programs, but also by a mixture of news and comedy repeats.

The top four spots on the week’s cable rankings in the 18-49 demo, on the other hand, were from original scripted dramas: USA’s “Burn Notice,” TNT’s “The Closer,” Lifetime’s “Army Wives” and USA’s “Psych.”

And these are merely some of the shining stars in what has become cable’s brightest summer to date, including high-profile newbies like “Saving Grace” on TNT and “Damages” on FX and as well as returning skeins including FX’s “Rescue Me” and USA’s “Monk.”

Cable’s top original dramas are still no match for the top repeating broadcast dramas — although that could change in coming summers if recent trends continue.

The highest-rated episode to date of USA rookie “Burn Notice” (1.7 rating/5 share in 18-49, 4.41 million viewers overall), cable’s top drama in 18-49 for the week, ranked 41st for the week among all programs. In 18-49, it was surpassed by repeats of eight dramas on the broadcast nets.

TNT’s “The Closer” (1.6/5 in 18-49, 7.67m), cable’s No. 2 drama of the week in 18-49 and No. 1 in both adults 25-54 (2.3/6) and total viewers, is up by double-digit percentages in its third season. And in overall total viewers, its 7.67 million ranked 15th among all primetime programs last week, lagging six drama repeats on the Big Four.

Overall for the July 30-Aug. 5 frame, Fox continued to shatter network records with its 26th consecutive weekly in adults 18-49, according to Nielsen. Net’s 2.2 rating/7 share stood tall opposite rivals CBS (1.8/6), NBC (1.7/6) and ABC (1.4/5). Univision was fifth (1.2/4), followed by cable’s USA (0.9/3).

First-year broadcaster CW tied with the Turner cable duo of TBS and TNT for seventh (0.7/2).

Fox tied with CBS for the week’s lead in adults 25-54 (2.3/7) and won as usual in persons 12-34 (2.2/7 to a 1.7/6 for runner-up NBC). CBS took the crown as the most-watched network overall (6.5 million to 5.6 million for Fox).

Fox, which won in adults 18-49 on five of seven nights, was paced by “Hell’s Kitchen” (4.0/11 in 18-49, 8.59 million viewers overall) and Thursday’s results show edition of “So You Think You Can Dance” (3.5/11, 9.56m) — the week’s top two telecasts among young adults.

First-year skein “Don’t Forget the Lyrics” also continues to perform well on both Wednesday (3.0/8 in 18-49, 7.80m) and with a special hourlong seg kicking off Thursday (2.9/10, 7.73m).

Fox also claimed the week’s No. 1 comedy in 18-49 and younger demos with a special 9:30 Sunday episode of “Family Guy” (3.2/9, 6.54m).

CBS was led by editions of “Big Brother” on Sunday (2.8/9 in 18-49, 7.52m) and Tuesday (2.8/8, 7.12m), which tied as the week’s No. 12 program in 18-49. The reality vet enjoyed its best week this summer, with Sunday’s edition drawing the largest overall aud for any episode.

Setting the pace for NBC were top-10 performers “The Singing Bee” (3.2/9 in 18-49, 9.80m), “America’s Got Talent” (3.1/10, 10.76m) and “Last Comic Standing” (2.9/8, 6.79m), with “Talent” standing as the week’s most-watched program overall.

ABC was behind the pack once again, as the finales of “Shaq’s Big Challenge” (2.1/6, 5.47m) and “American Inventor” (1.7/5, 5.27m) failed to excite auds. Net was also dragged down by burned-off firstruns “The Nine” on Wednesday (1.0/3 in 18-49, 2.99m) and “Masters of Science Fiction” on Saturday (0.8/3, 2.73m).

Disney Channel, led by “Hannah Montana,” was cable’s most-watched network overall for a fourth straight week in primetime, averaging 2.97 million viewers to 2.58 million for second-place USA.

Also big among the younger set was Nickelodeon with its premiere of “Drake & Josh: Really Big Shrimp,” which averaged 5.76 million viewers Friday (Daily Variety, Aug. 7).

Other highlights included: Lifetime’s “Army Wives” (1.4/4 in 18-49, 3.71m) ranking as cable’s No. 1 program of the week in women 18-49 (2.3/6); TNT’s “Saving Grace” again performing well on Monday (1.3/4 in 18-49, 5.37m), retaining 81% of its 18-49 lead-in from “The Closer”); FX’s “Damages” (1.0/3 in 18-49, 2.93m) rising week to week in demos; and Style Network setting a record Sunday for an original series with the premiere of “Kimora: Life in the Fab Lane” (335,000 viewers overall).

Each adults 18-49 ratings point represents 1.306 million viewers. All data is based on same-day viewing estimates by Nielsen.