A non-reknowned overclocker going by the name of kris has submitted a validated CPU-Z result of an Athlon 64 X2 5000+ overclocked monstrously to 4851 MHz, which is nothing short of incredible from one of these chips given their tendancy to play up with cold bug issues and the like under extreme cooling.
Though there isn't any actual definitive proof as to the authenticity of this CPU-Z screeny, Nordic Hardware took it upon themselves to contact CPU-ID and get their take on it, of which they seem to believe is genuine.
Get the full story on it here.
According to the submission he used Abit AN-M2HD, based on the NVIDIA GeForce 7050 chipset, to reach this frequency. The AN-M2HD is a good board for overclocking, but we've never seen results like this with it. At the same time, he did not specify an e-mail for anyone to contact him, which makes it even more fishy.