Yea, this diodes look a lot different than mine back then. At that time it was simply plastic-case diodes (as above) and each diode had its own resistor so in case of a failure the others would continue to run. These seems to have 3030 and 3535 footprints and no current-swallowing resistors that only generate extra heat. I'm almost sure that you even have an additional heatsink installed and not just a fan blowing on the PCB. As long as the PCB stays let's say below 70°C it should last a few years.
Had two of this:
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I take very good care of my light as treat my honey baby
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each day only use light 18/6, sometimes 20/4 , when flower keep 12/12 as mars told, like a human it needs to have a rest enough, so once i touch the light‘s skin there is no heat, only one time i feel a little warm, but actually no problem. Think in this way, my light will last more longer. I am not sure it's 3030 or 3535 on the board, since they look very similar,actually i dont care this, probably you 're right there is any additional fan or heat-sink inside of light,I will not open the light to check, since my plants are under the lights now
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So long as the light works fine and no issue appears I will keep using it, if there should be any problem i will contact the mars to help me out and ask them to offer me 3 yrs warranty right away. I know most led light especially like the electrical product cannot be used as much long times as the sellers told, since the parts sometimes get damaged easily and w/h out exact reason, so that time You need to pay fee for exchange or fixed, even mars hydro led or like my apple cell phone,my TV, etc,,. i didnt mean say something bad to any sellers, I just tell the truth.
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you know the sellers needs to make money, if our products keep a long time in very good condition and still dont buy new of their products, how they sell out their products and even make money. so this like a game, you are willing to play it and you will follow what the most people do. People around you buy new stuffs then i buy, people says led light good, then i try LED... if they do whatever, probably i will follow. just a joke
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