Components and Design
The XP-90c heatsink comes packed in a traditional Thermalright cardboard box. Inside however, the heatsink is securely nestled inside a closed-cell foam insert and the hardware is packed in two small white cardboard boxes.

In addition to the XP-90c heatsink, the box also contains:
- K8 retention bracket with screws
- P4 retention frame and metal backing plate with screws
- Fan mounting wires (2 x 92mm) and (2 x 80mm)
- Foam fan mounting strips (2)
- Syringe of thermal grease
- Printed Installation Guide
- Thermalright logo sticker
The XP-90c is the same size as the original copper/aluminum XP-90 but weighs almost twice as much. Because of this additional weight, Thermalright includes a replacement P4 retention frame with metal backing plate.

As we mentioned earlier, the XP-90c does not come with a fan. For this review, I will be using four different fans, ranging from low speed — very quiet to high speed — very loud, to see how the heatsink responds to different rates of airflow.
The XP-90c incorporates the traditional Thermalright retention wire mounting scheme to hold the fan in place. Two sets of wires are included; one set for 92mm fans and the other set for 80mm fans. The retention wires clip onto the base flange of the fan instead of reaching up over the top flange the way they did on earlier Thermalright heatsinks.

Having the clips attach to the lower flange eliminates the problem of having various mounting holes in the heatsink body to accommodate fan frames of different thicknesses. It also makes the upper flange accessible for attaching a wire fan guard (typically not so easy to do on earlier designs). There is a catch however; fans with solid frame bodies won’t work (unless you grind out an area for clearance).
The XP-90c base has two spring-steel clips attached for mounting the heatsink into a standard P4 retention frame. The included K8 retention bracket replaces the stock AMD bracket when mounting the XP-90c onto a K8 platform. An optional P4-LGA775 mounting bracket is not included but can be purchased separately. The base has an excellent machined finish and appears to be flat.
There are 28 copper fins that extend all the way down to the copper base, where they are soldered on. An additional 21 fins fill out the upper fan deck area, which provides a large surface area for heat transfer (49 copper fins total).

Thanks to the XP-90c’s compact size, this cooler is able to fit virtually all of today’s popular P4 and K8 motherboards.
Four heat pipes are used to effectively transport heat out of the copper base directly to the large fin area bellow the fan for maximum heat dissipation.



this is very nice , i think i
this is very nice , i think i want to get this for my rig im trying to build
Just like your comment was some 10 years late, mine is about 4 years late but yes, this is a great heatsink which unfortunately isn’t manufactured anymore as tower coolers and AIO liquid coolers dominate the market these days. So, even if you could find one online, and you certainly could as I have a 10+ year old Thermalright Ultra 120 Extreme that I can’t part with because it’s an awesome product and it even supports newest motherboards with adapter brackets, you need to do the same and figure out a way to mount this cooler to your motherboard.