A funny thing has happened to CPUs, their not as hot as they used to be. In some cases, Intel Core 2 Duo processors are pushing out as little as 65W, while some Celeron chips output just 35W of heat! It's quite a change from the long standing belief that newer processors will always output more heat. Die shrinks, moving from 90nm to 65nm, and now 45nm, mean more circuits are packed into ever decreasing spaces. Smaller circuits are more efficient, consequently electrical requirements and the subsequent heat output falls.

What does this mean to you? It means you should know your processor's TDP (Thermal Design Power) before going heatsink shopping. Take for example the heatsink Frostytech is testing today. This is a fairly compact socket 775 cooler, made just of extruded aluminum with an 80mm fan atop. The Glacialtech Igloo 5058 Light E is rated for 35W Celeron, 65W Core 2 Duo and 95W Core 2 Quad processors... though it would be hard to imagine anyone replacing the boxed Quad-core heatsink for something as basic as this. No, I think it's best to look at the Glacialtech Igloo 5058 Light E as a compact and quiet heatsink for energy efficient heatsinks in the 65W region.

Glacialtech's Igloo 5058 Light E heatsink stands a squat 55mm tall and comes with a fixed speed 80mm fan that rotates at a quiet 2600RPM. Weighing in at a feather 263grams, the Igloo 5058 is compatible with Intel socket 775 CPUs outputting 95W heat or less. Though for the best results, we'd change that to 65W or less.

Glacialtech Igloo 5058 Light E Heatsink
	HEATSINK SPECSHEET Manufacturer: Glacialtech Model No.: Igloo 5058 Light E Materials: extruded aluminum Fan Mfg: Powerlogic PLA08025S12H Fan Spec: 2600RPM, 12V, 0.17A Fan Dim: 25x80x80mm Heatsink & Fan Dim: 55x89x89mm Weight: 263 grams Includes: thermal compound, instructions Compatible with Sockets: LGA775 Est. Pricing: $20USD ($20CDN)

There's not a lot else that needs to be said about the Glacialtech Igloo 5058 Light heatsink, other than to reiterate that it's best suited to smaller enclosures where vertical height is restricted, and to energy efficient processors that don't run very hot. It should be suitable for 65W or 35W processors, but it is not suitable for 150W CPUs at all.

Base Finish and Flatness

Flipping a heatsink over to inspect the business end is often a simple indicator of overall cooler quality. More practically speaking, a heatsink is in many ways only as effective as the contact it makes with the processor - the flatter and smoother the better. Base finish is one of the criteria that Frostytech measure in the course of evaluating heatsinks, and it involves two distinct aspects. Surface Finish is the first; this is calculated with the aid of Surface Roughness Comparator that has a cross section of common machine surface finishes and their numerical surface roughness equivalents in microinches. The second is Surface Flatness. This is tested with an engineers straight edge or proven flat surface, in two axis.

FrostyTech's Test Methodologies are 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 its performance in the thermal tests!