top-down blowing design?

Too, there are major differences between the 990FX and the 990X that AMD chose to state only boards with the 990FX.

wardog wrote: From the above instruction sheet. I hi-lited two lines that AMD wrote: AMD FX??000 Series Processor System Requirements: AMD FX 9000 series processors feature a 220W TDP and have three unique requirements: 1. A robust CPU liquid cooling system. The Antec Kuhler H20 925, Cooler Master Nepton 120XL, and  Corsair H80i are examples of products with sufficient cooling capacity. 2. A socket AM3+ motherboard that supports processors with a 220W TDP. As of September 15, 2015,  the compatible motherboard list is as follows: ??Asus Crosshair V Formula-Z ??Asus SABERTOOTH 990FX R2.0 ??Asus M5A99FX PRO R2.0 ??Gigabyte 990FXA-UD3/Gigabyte 990FXA-UD3 R5 ??Gigabyte 990FXA-UD5/Gigabyte 990FXA-UD5 R5 ??Gigabyte 990FXA-UD7 ??MSI 990FXA-Gaming ??Asrock 990FX Extreme9 ??Asrock 990FX Extreme6 ??Asrock Fatal1ty 990FX Professional 3. Chassis exhaust fan mounted near the motherboard VRM components with at least  35CFM of air flow capacity.

There we have it, from the fine (or hard to find) print!

Thank you SO much wardog, for finding and posting this information!

IMO, the link to the FX-9000 Installation Guide should be included in a sticky post in the AMD Technical Support forum. It may not be what some people want to know, but it is what they need to know.

This statement alone warms my heart: "AMD FX 9000 series processors feature a 220W TDP and have three unique requirements:"

They used the 'R' word, Requirements.

Some of the wording may be loose, I agree, but IMO there is one big ambiguity:

2. A socket AM3+ motherboard that supports processors with a 220W TDP.

What is it about an AM3+ board that allows it to support a 220W TDP processor?

Let the arguments begin. I will try to stay out of that.

The point most dear to me personally: 3. Chassis exhaust fan mounted near the motherboard VRM components with at least  35CFM of air flow capacity.

Notice this requirement does not take into consideration the heatsink, or lack thereof, used for the VRM transistors. That does not make it something that can be ignored.

These requirements are kept at a high level, meaning lacking details. Still, they are not just very important. They are requirements. If you do not fulfill these requirements, and have problems, the fault is yours.

The only thing I would question, in theory shall we say, is why is only the 990FX chipset implied as a requirement. I know why it is to some degree, but I don't know why it would seem it is the only chipset worthy of use with a 220W TDP AMD processor.

Apologies, I read parsec's post all wrong. I thought he was referring to the use of top-down blowing desing, when he was in fact referring to reading the fine print. I also somehow managed to skip over the text after the big image, which would've revealed my error before posting. In short, we all agree on the subject.

parsec wrote: Are the 990FX board's VRMs exempt from needing extra cooling? The top-down blowing cooler warning is not mentioned in the 990FX Extreme9 CPU support list, but is included in the 990FX Extreme6 CPU support list, along with the AIO cooler warning. The 990FX Extreme9 has a more robust VRM heatsink, but lesser boards don't.

The Extreme9 also has a 12+2 power phase design, whereas the Extreme6 has 8+2. If I'm not mistaken, the heat load per channel scales pretty much linearly, so that with an 8+2 power phase design each channel has roughly half the heat load than with a 4+1 power phase design. Those extra channels probably go a long way in managing an FX-9xxx CPU. I would also expect the VRM section to be built of higher quality components than on lesser boards. Combining all this with that larger heatsink, it might even be possible to run those beasts on this motherboard without spot fans on the VRM. Strong emphasis on the word "might", though. ;)

PetrolHead wrote: I agree with wardog,  ....

Yea. It doesn't look bad. But OP, keep a close watch at how hot the VRM sinks are.

PetrolHead wrote: OT: "It is important when using an FX-8000 or FX-9000 series CPU." Not really true for the latter. There's a reason AMD provides a stock liquid cooler with those CPUs; air cooling is just not enough for that CPU (at least not with something that fits in a normal case). The motherboard needs to be cooled using something else than a top-down blowing CPU cooler.

I think more to parsecs point is that an extra fan (jury)rigged to blow over the VRM section is practically a must. More so with boards that are 4+1 and even some cheaper 8+2 boards with no or even skimpy sinks covering them.

Has anyone here ever read what the instruction that come with the included water coolers that come on the high end FX silicon? It'd be really interesting to see whether AMD themselves, like practically everyone else does, not mention additional or supplemental VRM cooling.

http://www.deepcool.com/product/cpucooler/2013-12/7_481.shtml

I'd like to think you'd be ok using this.

It's rated for the FX 8-cores and that overhanging fan on the bottom should blow some in the direction of the VRM section anyway.

parsec wrote: WOW, someone actually read the fine print in the CPU Support list!! bjlockie, good for you, most people don't even notice that. It is important when using an FX-8000 or FX-9000 series CPU.

Indeed.