I just installed a new Thermaltake 630 Watt smart series in my Inspiron 620 and also a Zotac GTX 560 and The power supply and video card preformed like a charm for about two days until on the third day of owning them my computer would not power back on the power light on the front would just flash orange any suggestions. I took out the new power supply and replaced it with my old one and computer runs fine.
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That Thermaltake 630 Watt model is made by HEC/Compucase for Thermaltake. That's exactly the type of crap reliability I would expect from HEC/Compucase made power supplies.