I'm not planning a new build (neither money nor necessity) but I like to be up to date and I'm seriously worried about one aspect of modern powerful builds: heat dissipation. I think this aspect must be covered in this build. A watt is a watt regardless of brands, quality, etc
I've not read the whole thread but one of the gfx cards mentioned consumes it alone (600 W) as double as my most powerful "heater" ever (330 W, Phenom II 125W + HD4890 190W theoretically, in practice I'm sure my sample didn't surpass 140W, 330W measured outside the PSU, what means the parts were getting about 270 W; in this age the TDP spec used to be higher than real consumption in general).
Dissipating 125W and 140W w/o excessive noise is easy. I got the impression (wrong?) that 125-150W is the limit for air, you'd need water beyond that.
But not only water. You need heatsinks (2 for say a 200W processor and a 600W vcard) and several fans per heatsink in the worst case. The water does only transport the heat to a more convenient place, why more convenient? Because in the destination you can fit a huge heatsink and several fans that you simply cannot fit close to the chip.
In theory 200W needs 2x120mm fans and a heatsink double as big (240x120mm) as a typical "normal" one for 100-125W?
In theory 600W needs 4-5x120mm fans and a heatsink quadruple or quintuple as big (480-600x120mm) as a typical "normal" one for 100-125W?
(I know there're 140mm fans available, that should be preferred to these, provided they've used the higher size to increase airflow, instead of to get quieter fans; simply I don't have experience with 140mm fans)
If you have a "classic wattage" processor and a "semi-modern wattage" GPU (up to 450 W), you can use a case with top mountings for a 360x120mm heatsink and 3x120mm fans for the GPU and any good "classic design cooler" for the processor, I've seen such cases, but I haven't seen one that can attend two multi big fans heatsinks, one for the CPU and one for the GPU.
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Predictably I would never use an "irrational" GPU, but I fear the following about processors (all this can be bad info, I'm just asking): they can have a TDP that is valid 90% or 99% of the time, say 120W, but the remaining 10% or 1% it's 200W (turbo mode etc). The 2nd spec is relatively hidden (it isn't called TDP). Whatever the name, you'd need cooling for 200W, not for 120W. Does this exist at all?
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I use Gigabyte boards for my 3 desktops, all old and 2 of them 2nd hand (one of them uses DDR2). When buying 2nd hand you try to hunt opportunities so this is likely a coincidence. Last time I chose brand and model of a new motherboard I compared photos from 2 or 3 mobos with the same chipset and I chose the one that had, in my opinion, better layout and cooling. I'm not very knowledgeable about Intel or AMD, I'm listening about that.