Both cards are too power hungry, hot and loud...Especially the HD6990 when it comes to cooling noise, with roughly the same performance being acheived with a pair of GTX570's or a pair of HD6950's for less money, and less hassle getting higher overclocks since they're still using about 200 watts a piece, so the cooling doesn't need to work as hard.
Pass on both the HD6990 or the GTX590 as i don't want 450 watt furnaces in my PC...
