From a list of 8 reference heatsinks the Thermaltake Volcano 6Cu+ managed to come in at position 6 - not the best, but by no means out of scale. Its' performance on the larger interface die was very good, scoring it at about the third position in that case. But as we rank our results according to the small interface die currently the heatsink shall remain a good performer, above OEM class, but not quite at the performance level - at least for small die processors like the T-Bird.

The extruded fan mount is good at keeping the fan solidly in place, and also helps to direct the exhaust air flow laterally, instead of through the clip opening. The copper slug which has been set into a milled hole in the base of the extrusion is of questionable usefulness as it only appears to make intimate contact around the edges.

Overall, the Volcano 6Cu+ would be a good heatsink to consider for a socket 423 Pentium 4 (assuming you are comfortable with the less secure socket-only clip, and absence of support for the heatsink retention mechanism), and an alright choice for any of the current bare silicon processors out these days.