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Sapphire Radeon 4870 fan speed too slow


New Member
Jan 2, 2007
15 (0.00/day)
Hello, i've been through some problems with my Sapphire 4870 (Click too see).
I used to manage the fan speed through ATI Tray tools and in 100% it was really noisy and the speed was around 2500-3500 RPM (don't remember exactly). But, from some days now, in 100% it reaches only 900-1000 RPM. I can't play any games because it goes to 100 Celsius+ in few minutes.
I tried removing all the fan things and realised that the fan bearing was moving smoothly, so I don't think it's the friction that is causing the slow speeds. Despite that I oiled the bearing to ensure that it was not the problem. But the problem persists.
I have no idea if the problem is the VGA not passing enough power to the cooler or the cooler itself.
Any ideas?

May 18, 2010
3,416 (1.22/day)
System Name My baby
Processor Athlon II X4 620 @ 3.5GHz, 1.45v, NB @ 2700Mhz, HT @ 2700Mhz - 24hr prime95 stable
Motherboard Asus M4A785TD-V EVO
Cooling Sonic Tower Rev 2 with 120mm Akasa attached, Akasa @ Front, Xilence Red Wing 120mm @ Rear
Memory 16 GB G.Skills 1600Mhz
Video Card(s) ATI ASUS Crossfire 5850
Storage Samsung 1Tb EcoGreen hard drive
Display(s) Hanngs-G 19"
Case Antec VSK 2000 Black Tower Case
Audio Device(s) Onkyo TX-SR309 Receiver, 2x Kef Cresta 1, 1x Kef Center 20c
Power Supply OCZ StealthXstream II 600w, 4x12v/18A, 80% efficiency.
Software Windows Vista X64
Buy a new cooler, it sounds like its dying. Look up the Accelero L2.