Susie, when you smoke at low temp, like that, you may want to use chips, or (as I do), sliver your chunks. I usually split a chunk into about 1/4" slivers, which smoke faster and you get it all.
Something not normally recommended, that you can try (for a "special case," like steaks), is to pre-heat the smoker and get the smoke rolling before adding the steaks. You will save a lot of warm-up time, since you're only smoking for around 45 minutes. For a short, low-temp smoke like steaks, it actually may be your best option.