很多品牌的服务器对会对第三方pcie设备进行检测，如果检测到非认证设备，散热系统会按较高转速运行。最近购买的一台戴尔T140服务器在插上一张显卡之后也出现了风扇转速高噪音大的问题。经过百度，网上的解决办法都是通过ipmi命令设置风扇转速模式，尝试后发觉不行，应该是新款服务器不再接受这样的命令。转到Google之后终于找到解决办法，可行。

原理是从racadm命令行更改第三方pcie卡所在插槽的LFM模式。

戴尔官方论坛链接：https://www.dell.com/community/Power-Cooling/How-Do-I-Disable-The-Third-Party-PCIe-Card-Default-Cooling/td-p/8089455

戴尔官方关于服务器散热模式的白皮书：poweredge_pcie_cooling

When iDRAC unsupported hardware is installed, it will run cautiously and its fans high as a cooling measure. In 14G, can you try the following commands;

Also you can review this article “PCIe Card Cooling with Dell EMC
PowerEdge Servers”   https://dell.to/3lgCwHr

system.PCIeSlotLFM.x.3rdPartyCard attribute. You will need to modify "x" with 
the numerical value of your PCIe slot.

racadm>>racadm get system.PCIeSlotLFM.3.3rdPartyCard
[Key=system.Embedded.1#PCIeSlotLFM.3]
3rdPartyCard=Yes
racadm>>

If the value for this slot = yes, then you can disable the Dell EMC cooling 
algorithm for that slot. You will need to modify the 
sytem.PCIeSlotLFM.x.LFMMode value (x = slot numerical value).

racadm>>racadm set system.PCIeSlotLFM.3.LFMMode 1
[Key=system.Embedded.1#PCIeSlotLFM.3]
Object value modified successfully

racadm>>racadm get system.PCIeSlotLFM.3.LFMMode
[Key=system.Embedded.1#PCIeSlotLFM.3]
LFMMode=Disabled
racadm>>