4670 is a good choice gigabyte reviews
put together a shuttle xpc and bought this card based on its low power consumption and size. It is recommended to use a 400 watt power supply with this card but my shuttles 250 watt psu is running it just fine under windows XP
sapphire makes a good card gigabyte asus they all should run cool http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Mine idles at 38-39. The hottest it has ever gotten is 62 at 30% fan speed after Folding@Home for 12 hours lol.
And for comparison's sake the Geforce 8600 GTS in my old comp idled at 53 and stayed around 80 under load at 75% fan speed lol.