CoolJag JVC661A V-Type Pentium 4 Heatsink Review

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Countless heatsink designs have been cast into aluminum in an effort to meet the requirements of both low cost and high thermal efficiency. Aluminum extrusions have typically been the most popular option, but within the last year and a half skiving has come to market and been adopted widely.

CoolJag are only the latest in a short list companies to make use of the process, and the CoolJag JVC661A even takes things one step further. New techniques and technologies are something we look forward to, so what is it about the JVC661A that makes it different from the pack?

All skived heatsinks up until now have been based on right angles - the fins meet up with the base at a nice 90 degree junction. While this is still actually true, the JVC661A leverages the base adjacent to a central V-shaped channel up 15 degrees or so. In other words, the fins meet up with the base at a right angle, but the base angles up towards the center.

Enter the"V-Type" skive heatsink you see to the left. The triangular shaped base and V-shaped cut out in the skived fin are intended to improve thermal performance by aiding the exhaust air path to the surrounding environment. As we move forward with the testing of the CoolJag JVC661A it will be interesting to see just how this new design adaptation works to improve or inhibit thermal efficiency.... among other points of consideration.

	Heatsink Specsheet: Model: JVC661A HS Material: Aluminum skive Fan: Everflow, 5000 RPM, 12V, 0.28A Fan Dim: 15x70x70mm FHS Dimensions: 83x65x61mm Weight: 377 grams Made by: CoolJag Sold By: www.cooljag.com

Cooljag JVC661A Heatsink From All Angles
	The Fan: The 70mm Everflow fan measures 15mm thick and sports an eleven bladed impeller. The fan produces very little noise and draws 0.28A. Attached directly to a metal fan shroud, the connects to the motherboard fan header for power and supports RPM monitoring.
	Heatsink Top: With the fan removed we find a 4mm space between the base of it and the tips of the fins. Both fins angle inwards to where the clip is located, and the base rises up in a triangular fashion. It is hard to say what this open space will add to the overall thermal effectiveness of the JVC661A, but since this area is directly under the fan motor there is little likelyhood that anything will be lost either.
	Side A: The clip connects to four external catches which hook onto the pentium 4 HSRM. There are 40 aluminum fins of 31mm in height which are spaced 1mm apart. Fins measure on the order of 0.3mm thick. The base is thicker at the center of the heatsink, but at the edges measures 9mm thick.
	Side B: The clip mechanism which is used to lock onto the HSRM is simple and pretty effective. Each corner has a small tab which locks into the plastic tab to hold the JVC661A firmly in place. The force is applied to the center of the heatsink so if the P4 is not positioned squarely in the center of the HSRM there is a chance the heatsink may sit crooked.
	Heatsink Base: We measured the base with a straight edge and found it to be very flat and smooth. There are machining marks visible on the surface but none of them are particularly deep.