The Rosewill RCX-Z2 heatsink is designed for socket 775 Intel Pentium D and Core 2 Duo processors, and as with most heatsinks vying to push the stock Intel heatsink out of the PC, it comes equipped with a Pulse Width Modulation (PWM) fan. The fan on the RCX-Z2 spins at speeds of 500-3400RPM, and is internally illuminated with blue LEDs. The fan motor is suspended from the frame, and this is called an open fan frame style. It yields quieter operation and better airflow at reasonably low impeller speeds, as would happen with PWM fan whose velocity is controlled by the computer BIOS.

Pulse Width Modulation compatible fans are noted by their 4-pin power connectors, and what PWM does is enable the BIOS to directly control fan speed. The impeller speed increases or decreases relative to the processor's temperature at any given moment, in this case between 500RPM and 3400RPM.

When the Rosewill RCX-Z2 heatsink is used with a motherboard that does not support PWM, the fan rotates at full speed. At full tilt (3400RPM) the heatsink produces 59 dBA noise. The Rosewill RCX-Z2 is identical to the Akasa AK-961 heatsink, which FrostyTech has reviewed previously.

Rosewill RCX-Z2 Heatsink
	heatsink specsheet manufacturer: rosewill model no.: rcx-z2 materials: 52 aluminum fins, copper heat pipes, copper base fan mfg: n/a fan spec: 500-3400rpm, 12v, 0.25a fan dim: 25x90x90mm heatsink & fan dim: 71x96x95mm weight: 380 grams includes: thermal compound Compatible with Sockets: LGA775 Est. Pricing: $25USD ($29CDN / 12GBP)

Rosewill's RCX-Z2 heatsink is made from a collection of 52 thin stacked aluminum fins with zippered interlocking tabs, three copper heatpipes, and a small block of copper at the base. The aluminum fins are rather squat, measuring just under 35mm tall, but that gives the heatsink a compact profile. The aluminum fins aren't nickel plated, so heatpipe-to-aluminum fin joints are not soldered. Hopefully the joints aren't loose, or thermal transmission will suffer. The three 6mm diameter heatpipes are soldered to the copper base.

The 90mm fan has four internal blue LEDs to illuminate the blue plastic. The lights are pretty small, but the effect is nice. The fan mounts on posts spaced 80mm apart, with little plastic clips that grip the fan frame. Intel's reference tool-free plastic snap clips are used to install the Rosewill RCX-Z2 heatsink. The heatsink ships with a small syringe of thermal compound.

FrostyTech's test methodology is outlined in detail here if you care to know what equipment is used, and the parameters under which the tests are conducted. Now let's move forward and take a closer look at this heatsink, its acoustic characteristics, and of course it performance in the thermal tests!