For each of the past five years, I've attended MusicfestNW, a multi-genre live-music extravaganza that features 200 bands playing at more than 20 venues across Portland over five nights.

Until just a few weeks ago, though, I didn't realize that MFNW is the third-largest indoor music festival in America, right after SXSW in Austin, Texas, and the CMJ Music Marathon in New York City.

SXSW and CMJ are industry schmoozefests, both known for their ability to catapult bands from obscurity to next-big-thingdom.

MFNW isn't that way. It's more focused on performances than shaking hands and signing deals. But that doesn't mean I can't treat it as my own personal land of discovery. After all, Bend gets a lot of great shows, but it's rare we get an appearance by a band that's buzzing on a national scale.

The 2011 version of MFNW — held Sept. 7-11 — featured some big names: Band of Horses, Iron & Wine, Explosions in the Sky, Macklemore, The Kills, Blind Pilot, Blitzen Trapper. I saw only one of those; Explosions in the Sky was effortlessly epic as usual, especially in Pioneer Courthouse Square against the gorgeous lights of dusk in downtown Portland.

Instead, I spent my MFNW seeing veteran artists like reunited indie heroes Archers of Loaf, R&B/soul guitar legend Dennis Coffey, Australian cult stars You Am I and punk icons OFF! and Ted Leo. And when I wasn't doing that, I was digging deeper into the schedule and showing up early to venues to see up-and-coming acts.

Three stood out as extremely promising, while three Portland bands showed why that scene continues to turn out big-time success stories. Here's a quick roundup:

• I've had “In Light,” the debut album from Givers , in heavy rotation for a few months now. But it did not prepare me for the live power of this Louisiana-based band.

For two solid hours, Givers was explosive, emotional and totally satisfying. The fresh-faced quintet — led by Tiffany Lamson and Taylor Guarisco — is a joy to watch, and they flavor their indie-pop with African and Zydeco sounds, like a female-fronted Vampire Weekend that oozes Southern charm rather than Yankee smarm. Bouncy tunes like “Saw You First” and “Ceiling of Plankton” are pleasant on the record, but on Friday night of MFNW, they turned the normally chilly Doug Fir Lounge into a sweltering, exuberant dance party. It was the best and most surprising set of my weekend.

• Purity Ring is smartly following the current path de rigueur to buzzy Internet fame: host an inscrutable Tumblr, release songs sparingly and online, stay mysterious, then watch the synth/fuzz-obsessed music blogs fawn.

In most cases, the fawning is unwarranted. But this is not most cases. On Thursday night at the Doug Fir, Corin Roddick and Megan James played a set as oddly beautiful as the three songs they've put out into the world. Roddick played a series of pipes joined together and connected to a mixer; each tap produced a synthesized sound. He used the mixer to produce on the fly, chopping up beats and James' icy, ethereal vocals to create a stuttering blend of indie-pop, hip-hop and dubstep. The duo calls their music “future pop,” a descriptor that is not only a tad presumptuous, but also totally apt.

• Before the New York band White Hills took the stage Saturday night at Ash Street Saloon, it was clear this was going to be a big show. Frontman Dave W.'s face was painted silver, while bassist Ego Sensation (a she) wore tight, shiny red pants and glittery shoulder armor.

The band did not disappoint, cranking out thick, swaggering slabs of heavy psych that burrowed down into a subterranean groove and stayed there until it was time to blast off into space aboard one of Dave W.'s limber solos. It was noisy. It was pummeling. It was awesome enough that I bought a White Hills T-shirt that won't fit for more than I should've paid. It has some sort of weird mushroom world on it.

• Among the Portlanders, a quick shout-out to the snappy soul band Monarques , the spastic pop-rockers in Archers and master songcrafter Holcombe Waller , all of whom should be huge. The Rose City's talent pool is seemingly bottomless, much like MusicfestNW, where some of the best stuff can be found in the more uncharted areas of the schedule.