The Xigmatek HDT-S1283 heatsink features three heatpipes in direct contact with the top of the processor, resulting in one very potent CPU cooler. The technique is called Heatpipe Direct Touch, and for today's class of heatspreader capped processors it's the only way to go.

If you take the Xigmatek HDT-S1283 and flip it over you'll see an aluminum base with three wide grooves cut into it, set snugly within these grooves are large diameter flattened copper heat pipes. The heatsink has no heavy copper base plate, instead heat is conducted directly from the core of any K8 AMD or LGA775 Intel processor to the 8mm diameter heatpipes directly. The heatpipes transfer that heat directly to a large aluminum fin cooling tower above. It's a very simple heatsink, distilled down to the most basic components that influence thermal performance, and that is why the Xigmatek HDT-S1283 succeeds.

For the uninitiated, take note of the relative newcomer Xigmatek Co., Ltd. Each heatsink this company has introduced thus far has been geared towards lower noise, contained some form of innovative cooling technologies, and with one exception has performed very well.

The Xigmatek HDT-S1283 heatsink FrostyTech is reviewing today is equipped with vibration absorbing rubber fan posts, a 120mm PWM fan that scales in speed from 1000-2200RPM, and a little spoiler to direct exhaust airflow down towards adjacent motherboard components. The 600gram HDT-S1283 heatsink is compatible with socket 775 Intel Core 2 Duo/Quad CPUs, and all socket 754/939/940/AM2 AMD Athlon64/Phenom processors. Small formfactor owners are going to be out of luck as the Xigmatek HDT-S1283 heatsink stands 160mm tall, but for the rest of us its'$55CDN ($55USD) price tag is well worth the investment.

Xigmatek HDT-S1283 Heatsink

heatsink specsheet manufacturer: xigmatek model no.: hdt-s1283 materials: aluminum fins, copper heatpipes, aluminum base with exposed heatpipes. fan mfg: xigmatek ad1212hx-a7bgl fan spec: 1000-2200rpm, 12v, 0.44a fan dim: 25x120x120mm heatsink & fan dim: 160x120x77mm weight: 600 grams includes: lga775 and k8 socket mounting hardware, spoiler fin, thermal compound, instructions Compatible with Sockets: 754/939/940/AM2, LGA775 Est. Pricing: $55USD ($55CDN)

First off let's look at Xigmatek's "Heat-pipe Direct Touch". This is one of the main reasons the HDT-S1283 heatsink handles the way it does, and essentially it describes how the copper heatpipes come in direct contact with the top of the processor. This arrangement minimizes thermal resistance as heat energy is conducted directly to the heatpipes, rather than through some intermediary heatspreader. The 8mm diameter heatpipes thread up through the many aluminum cooling fins of the HDT-S1283 heatsink where heat is quickly and efficiently dissipated into the surrounding air mass.

Xigmatek have built the HDT-S1283 heatsink with widely spaced aluminum fins so that lower velocity air can pass through the heatsink with less resistance. A removable aluminum spoiler has also been included, it slots into the back of any of the fins to direct some airflow up or down. This is useful if you want to cool nearby motherboard components like MOSFET heatsinks, for example.

The aluminum spoiler is an innovative idea, but when the HDT-S1283's fan is spinning at its slowest speed the usefulness does come into question. The 120mm PWM fan is held in place on the aluminum fins of the Xigmatek HDT-S1283 heatsink with four vibration absorbing rubber mounting posts. These fit through the standard screw holes in a vaneaxial fan frame, and keep the fan elevated 2.0mm away from the metal. If the fan motor happens to develop vibrations down the road, the rubber 'shock absorbers' can reduce that from becoming noise.

The Xigmatek HDT-S1283 heatsink ships with brackets for LGA775 and AMD K8 processors (754/939/940/AM2 respectively). The Intel socket 775 clips use the standard push-to-lock plastic clips that insert into the four motherboard holes around the processor socket. AMD Athlon64 processors on 754/939/940/AM2/AM2+ work with a modified spring clip that attaches to the lugs on the AMD heatsink retention frame. A cam lever at one end of the clip applies pressure to the heatsink base directly. The AMD clip is tool free, but the metal is thin and tends to bend towards one side or another after clamping pressure is applied.

The Xigmatek HDT-S1283 heatsink will be tested on FrostyTech's Intel LGA775 and K8 version of the Mk.II synthetic thermal temperature test platform, and compared against several reference LGA775 and K8 heatsinks. The whole test methodology is outlined in detail here if you'd like to know what equipment is used, and the parameters under which the tests are conducted.

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.

The Xigmatek HDT-S1283 heatsink has a surface roughness of approximately 32 microinches, which is considered good. The base itself has a smooth sanded finish and is generally flat in both axis. There are six small voids created where the copper heatpipe meets up with the aluminum mounting block, but these serve a positive use when the heatsink is clamped down by allowing excess thermal compound to evacuate itself from between the heatsink and processor. The copper and aluminum parts were flush on the unit Frostytech tested.

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!