I have a home/business computer and is looking to upgrade it so it can run the latest games with okay quality and do schoolwork. For instance, I want to play BF3 on the lowest and have 1680*1050 resolution. Here's my computer:
I can't say for certain if it is or is not reliable when it comes to the power supply in your machine but you can decide on a different brand of this card to your liking. There are driver related problems with AMD and Nvidia these days so it is a guessing game of which driver revision works best.
GT440 192bit isn't bad for the price but for that price you can do better. It is based on the same core as the GTS450 but just cut down. I would go for it as it doesn't need a 6pin power connector. Keep in mind that it looks cheaply built and will get dirty pretty quickly but it will beat the Kepler based cards in the same price point.
For $100 you can get a faster card like a used gtx460 if you are lucky (a beast of a card at that price) but if you want new then a gts450 or a gtx550ti if there is a sale. As for amd a 6670 if you want to be saving a little but a 6750 is a little faster. If you are able to swing a few extra bucks then a 7750 hands down. It is almost as fast as a gtx460 but uses hardly any power and runs off the slot alone. At idle it uses almost no power at all, try around 4-8w!
Used cards are always a gamble and a lot like buying used cars. Sometimes you get very lucky and other times there is always something that needs to be fixed. The gtx460 is a odd card, if the original owner ran it at stock fan speeds in a hot case but overclocked it like crazy it isn't worth it. These cards have issues with the power vrm overheating if there is no heatsink to cool it and the memory doesn't like getting hot so people have issues. I got one and using it now, its almost two years old but it is modded and is rock solid.
You can mod one pretty easily in under 15min and likely it will last a good two or three years.