nforce 4 definitely. The feature set on the K8T890 sucks. It was supposed to use the VT8251 southbridge, bringing SATA-II/NCQ, HD Audio, etc. Unfortunately, this southbridge has since dissappeared off the face of the earth, and all the current K8T890 boards use the old VT8237. nForce4, on the other hand, has SATA-II/NCQ, hardware firewall, nice software overclocking/monitoring tools (ntune), gigabit lan, etc. On top of that, performance and overclocking is pretty damn good. I was at one point looking forward to the K8T890, but considering how much of a joke the whole product line has been (lacking features, months of delays with no explanation, lack of any variety of retail boards), I have to say I'd avoid it like the plague.