I first became interested in quieting PC's about a year ago when I bought 2 new A64 3500+ PC's and was subjected to 5 fans going full-bore. Since then I have become somewhat obsessed with the idea of silent computing - (my definition of silence as opposed to 0db is "at least below the ambient room noise at the quietest time" or "inaudible from my usual working position - PC hanging below a desk"). Since then I have been busy with researching quiet components, work and a house reno but recently got around to actually quieting (it's not silent yet) my current rig.
Many thanks to the editors and contributors at SPCR, they are a terrific resource and community
Any further feedback and advice welcomed - this is definitely a work in progress.
Here is what I bought in October 2005:
Motherboard: Gigabyte GA-K8N Ultra9 system board with Nforce4 Ultra chipset
CPU: AMD Athlon64 3500+ @ 2.2GHz
RAM: 1 GB DDR Kingston RAM ** Updated 1/1/2011 to 2 x 2GB - no new pics **
HDD: (Initially & in pics below) 2 x WD SATA II 250 GB 7,200 rpm in RAID 0 ** Updated 1/1/2011 to Corsair 120 GB SSD - no new pics **
DVD-RW: LG GSA-41697B
Graphics: PCI-X WinFast PX6600 GT 128 MB
Monitor: BenQ FP91G 19 inch (1280x1024) TFT LCD ** Updated 1/6/2012 to 42" LCD **
Mouse: LogiTech Wireless Click! Plus Optical
Keyboard: LogiTech Wireless ** Updated 1/1/2011 to Windows 7 64 bit Enterprise w SP1 - no new pics **
After the initial PC assembly and resulting ruckus, I decided to slow the fans down. Not knowing what I was doing, and not having discovered SPCR yet, I soldered a few different resistors to the different fans I had - a 120mm case fan, a 120mm PSU fan, an 80mm front intake fan (for cooling the HDD's) and the whiny GPU fan.
I experimented by supplying 12V off a battery and listening to free air noise until I was satisfied I had reduced the noise considerably. Generally I found around half the voltage, 6 to 7 volts, was best. I don't have sophisticated measuring stuff, just a multimeter and ears, so I can't say what the noise dropped from, or to. But it was a marked improvement and I never had any problems with overheating - the air coming out of the case was always quite cool and mobo utilities reported low CPU temps. As the mobo had a CPU fan ramp adjustment capability depending on thermal levels I was safe (I'd left the CPU fan alone anyway).
After a few weeks I found SPCR and read hundreds of threads, thousands of posts. Took weeks. I digested some ideas and made some minor mods:
I tried to get cool air directly to the CPU by modd'ing the chassis duct:
I had always tried to build neat PC's with cable folding and component placement, but was impressed by the cablegami skills on offer at SPCR.
So that was what I had up until last week.
Then I ordered some silencing gear - Scythe Infinity heatsink
which includes a quiet 120mm Scythe fan, Nexus 120mm, 92mm & 80mm fans, Flex noise absorption foam pads
, Zalman VGA Cooler ZM80D-HP
, Zalman Northbridge flower cooler NBF47
& soft silicone fan mounts
I spent all night (literally from 10pm until 7am, although I was working on other PC software builds as well) installing the new components, cleaning the PC (my reno has generated a lot of dust, especially very fine concrete dust) and taking photos, testing improvements one by one. So now Grumpy (my PC) looks like this:
I have gone from 5 fans (CPU, GPU, PSU, 80mm intake, 120mm exhaust) to a passive CPU, passive GPU and just 2 fans - a 120mm PSU fan (still undervolted via inline resistor to ~6V) which doesn't ramp up anyway so it's effectively silent / absent, and a single 120mm Nexus case exhaust fan running at 12 V hardmounted.
The noise level has dropped a lot, I just wish I could measure it. At night, I can just hear it (I live on acreage where it's pretty quiet except for some animal noises) when sitting at my desk. Disappointingly though, the noise quality has gone from a low frequency / wideband woosh, to a kind of thrumming. I have tried 2 x Nexus 120mm and both do the same thing. They look a bit unbalanced, if I spin it by hand I see a bit of movement which is absent on my other fans. I haven't tried all 5 fans I bought but I am not happy with the quality control. It might get better though if I 7V it, everyone else at SPCR rates the Nexus 120mm Real Silent fans so I am hoping that makes a big difference. Otherwise I think I will put the original MEC case 120mm fan back in, or the replacement Scythe 120mm (the original with the Infinity heatsink had 4 broken arms on arrival), or maybe soft-mounting will help. I bought some silicone softmount grommets, but I have to mod the Nexus mounting hole corners to pull them through.
I am really happy with the new noise level. I can hear HDD's much more clearly now, when de-fragging it is the loudest noise for sure.
I couldn't fit the Zalman chipset flower heatsink due to the graphics card - the onboard one is reasonable but I thought taking away some fans I'd need to ramp up the NB cooling. I can't get a temp reading on this from the Gigabyte mobo utility.
Still to come is softmounting the case & PSU fan, ducting the Infinity to the case exhaust fan (my CPU temps are ~30 degrees doing office stuff, hardly seems worth it), ducting the PSU into a separate chamber (also hardly seems worth it given the fan hardly ever ramps up) and softmounting the HDD's. I have an idea for the HDD's using a DIY heatsink, and either elastic suspending them as others have done - but with a heatsink for better cooling - or using silicone mounting blocks
which supposedly stop vibration transfer to chassis. Kind of a cheaper and hopefully better solution than Zalman's ZM-2HC2
Here are my DIY HDD heatsink ideas - anyone recommend for or against a model?