FrostyTech Synthetic Temperature Test Platform Results
Mfg.	Model	Ambient Temp.	27mm large copper block	15mm small copper block		27mm large copper block	15mm small copper block	Thermal pad	No. Fans	Fan Noise	Clip force
			50W	50W		100W	100W
Thermalright	SLK800	21.7	34.8	37.5		45.2	51.6	none	1	loud	med
Thermalright	AX-7	21.7	34.8	37.1		46.1	52.1	none	1	loud	med
Tocools	Novasonic	22.9	40.9	39.9		54.4	59.4	none	1	med	stiff
Coolink	U1P2	26.1	39.4	44.9		50.9	62.2	none	2	loud	easy
Arkua	628	23.9	42.7	42.1		58.9	62.3	none	1	med	med
Thermal Integration	TI-V77L	26.5	39.1	44.4		57.5	63.6	grey	1	med	med
Sibak	AC02625B	23.2	41.3	59.0		43.2	64.7	none	1	loud	med
Sibak	AC06725TH	22.5	42.9	46.2		61.7	67.7	none	1	Very loud	med
Coolermaster	HHC-001	21.7	40.0	44.8		56.3	68.1	none	1	loud	easy
Dynatron	DY1206BH-625	23.2	40.0	55.1		47.6	70.4	none	1	loud	stiff
AVC	Tundra2	22.0	41.4	47.5		59.0	71.1	none	1	loud	stiff
Vantec	CCK-6027D	27.4	45.4	49.6		64.9	73.4	none	1	med	med
Akasa	Ag Mountain2Q	21.7	42.4	48.5		61.2	74.5	none	1	med	med
Coolermaster	HSC-V62	21.4	47.4	52.8		61.7	74.5	none	1	quiet	easy
NengTyi	XPC5000	23.9	46.5	49.1		69.1	76.1	none	1	med	med
Spire	5F263	22.6	44.7	51.8		64.3	76.2	white	1	low	med
Titan	TTC-CU5TB	24.2	46.2	51.2		61.8	76.4	none	1	loud	stiff
Eumax	EU01	22.6	43.5	50.2		60.8	77.1	none	1	med	stiff
Taisol	CGK760092	23.4	42.7	51.3		61.2	77.5	pink	1	low	med
Spire	5T235	22.3	43.0	50.3		62.8	78.1	white	1	med	med
Zalman	CNPS6000-Cu	24.8	46.4	53.8		65.6	78.2	none	1	very low	easy
Taisol	CMK702	20.6	40.8	48.7		61.6	78.4	none	1	low	easy
AVC	112AM1	24.8	46.6	52.9		70.1	79.6	none	1	low	stiff
Coolermaster	HHC-L61	21.5	47.2	48.3		71.2	82.3	none	1	quiet	easy
Spire	5U213C1H36	19.8	45.8	54.4		67.1	83.3	pink	1	low	easy
Thermaltake	Volcano 6cu+	26.5	40.3	55.3		58.6	84.4	carbon	1	loud	med
Akasa	AK821	22.7	49.4	57.2		74.1	93.2	grey	1	med	med
Verax	P11T	26.1	61.2	69.7		90.9	102.7	none	1	none	easy
Verax	P14	26.1	56.9	67.4		81.6	101.2	none	1	none	easy
			50W	50W		100W	100W

The final rise above ambient temperature results for the 5U213C1H3G heatsink are not too flattering despite its low noise fan and extruded aluminum heatsink with screwed on copper baseplate. While the retail price of a heatsink of this class is extremely competitive, the thermal results are not that exciting when the fan has no reason to spin at maximum RPM.

One of the reasons why we are not that keen on this type of dynamic cooling control is that for cases where there is good airflow, ambient temperature may not necessarily rise above 30 degree Celsius. While Spire do not mention the temperature threshold of the sensor, most seem to be set for the 35-45 degree region.

Had the temperature sensor been positioned in direct contact with one of the aluminum fins I think the Spire 5U213C1H3G could have performed quite admirably for an OEM heatsink. I'd recommend to anyone who is using this heatsink to remove the thermistor from its position at the side of the fan and reposition it between two fins at the center of the heatsink (under the fan motor). Noise levels will no doubt increase as will the cooling ability of the Spire FridgeRock heatsink.

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