Hey Ark,
LED's are great light sources but keep in mind, they too put out heat. The strips u are describing sound like regular 5mm, 10mm or superflux led strips. These leds would have to be in very large abundance to grow plants. You didn't mention plants, so a lot of LED's wouldnt be required. If you are looking to grow plants, the most efficent way would be to buy the galelio system which is rediculously priced but uses smaller led's like the 5mm or 10mm or make a light system yourself using high power 5 watt LED's, these however will run you over 100 or so to build it properly and give off a lot of heat, heatsinks are necessary.
Since you said nothing about plants, i am assuming it isnt a concern. This is fun because you have a large flexibilty with LED fixtures and types. Chances are you bought a really crappy brand of LED fixtures and LED's as well, having dealt with plenty of LED's, i know a good one from a crappy one, right on down to the color.
Personally, i buy 99% of my LED stuff from
www.oznium.com They have plenty of LED fixtures to choose from, very high quality merchandise, also note that flowlighting is the owners personally brand of light, of which i have bought and been quite satisfied with, i actually have an underbody car kit under my couch

and LED one of his, had it for 5 years already.