FrostyTech Synthetic Temperature Test Platform Results
Mfg.	Model	Ambient Temp.	27mm large copper block		27mm large copper block	Thermal pad	No. Fans	Fan Noise	Clip force
			50W		100W
AVC	117140	22.6	37.8		50.4	none	1	med	med
Coolermaster	IHC-H71	23.0	37.0		51.1	none	1	loud	stiff
Arkua	8568	22.4	37.8		51.7	none	1	med	med
NengTyi	XPC5000	23.8	38.4		53.9	none	1	med	loud
Alpha	PAL8942	27.9	42.6		54.0	none	1	med	med
Vantec	GSN-7025	22.5	41.7		58.5	none	1	med	med
Glacialtech	Igloo 3300	22.4	40.5		58.8	silver	1	low	easy
Chauh Choung	DTA-478	22.4	42.1		59.0	carbon	1	low	med
Taisol	CEP426151A	24.3	43.7		59.7	none	1	med	easy
Intel	Socket 478	22.4	41.8		59.8	carbon	1	low	med
Dynatron	DC1207BMW	23.2	42.7		61.1	none	1	med	easy
Titan	TTC-MT3AB	22.8	41.5		61.2	none	2	loud	stiff
Dynatron	DC1206BM-S	22.4	43.2		62.0	none	1	med	med
AVC	117160	22.4	42.7		61.1	white pad	1	med	med
Zalman	CNPS6500B-AlCu	26.3	42.9		61.3	none	1	low	easy
Cho-Liang	CL-CB00881	23.6	41.2		65.0	none	1	med	easy
Cho-Liang	CL-CB0307Z17	24.2	45.6		65.7	none	1	med	easy
Cho-Liang	CL-CB0094-1A	23.2	39.5		67.9	none	1	med	easy
Globalwin	VA476	28.7	49.5		68.0	grey	1	med	easy
Dynatron	DC1206BMV	23.1	45.1		68.2	none	1	low	easy
ChoLiang	Cl-CB0309Z17	24.3	46.7		68.6	none	1	med	stiff
Vantec	GSN-7015	22.4	47.5		69.0	none	1	loud	stiff
			50W		100W

Keep in mind that there are a lot of extra variables involved with the testing of Zalman heatsinks since they use a fan which can be in any number of different orientations. Depending on those orientations the thermal performance of the heatsink can vary, and if you have a good internal case flow that can also add to a performance increase.

Taking into consideration that the CNPS6500Cu is designed to be a low noise quiet cooler these results are pretty good. Generally speaking, quiet heatsinks perform quite poorly when stacked up against everyday performance coolers.

Rise Above Ambient Temp. (c)
Mfg.	Model	27mm large copper block		27mm large copper block
		50W		100W
Alpha	PAL8942	14.7		26.1
AVC	117140	15.2		27.8
Coolermaster	IHC-H71	14.0		28.1
Arkua	8568	15.4		29.3
NengTyi	XPC5000	14.6		30.1
Zalman	CNPS6500B-AlCu	19.5		34.8
Taisol	CEP426151A	19.4		35.4
Vantec	GSN-7025	19.2		36.0
Glacialtech	Igloo 3300	18.1		36.4
chauh Choung	DTA-478	19.7		36.6
Intel	Socket 478	19.4		37.4
Dynatron	DC1207BMW	19.5		37.9
Titan	TTC-MT3AB	18.7		38.4
Globalwin	VA476	20.8		39.3
Dynatron	DC1206BM-S	20.8		39.6
AVC	117160	20.3		39.8
Cho-Liang	CL-CB00881	18.2		41.4
Cho-Liang	Cl-CB0307Z17	21.4		41.5
Cho-Liang	CL-CB0309Z17	22.4		44.3
Cho-Liang	CL-CB0094-1A	16.3		44.7
Dynatron	DC1206BMV	22.0		45.1
Vantec	GSN-7105	25.1		46.6
		50W		100W

Overall we are very pleased with the updated version of the CNPS6500-AlCu which retails for around $40USD, and especially appreciate the new clipping mechanism. Things have changed only slightly from that earlier model, but as there are physical differences the two heatsinks should not be considered identical.

With a beautifully flat base, and a very low noise cooling solution the Zalman heatsink certainly fulfills a lot of criteria with a minimum of fuss. The only possible down sides are if the case you are using has the powersupply located over the processor. If that is the case you will not be able to use this heatsink at all. There just won't be any space for the fan to sit - and it must sit above the heatsink in order for the unit to operate properly.

Related Articles:

Here are a few other articles that you might enjoy as well...