Originally posted by: bunnyfubbles
Hey
Qbah, what about your powersupply? you can regulate the fans inside the case so much only to have your quiet be ruined by a relatively loud PSU unit
I also find it almost bizarre to read about what is considered to be normal temps for GPUs as my 4850 will idle at 30C and max in the low to mid 40Cs while gaming and topping out at 49C only through OCCT when stress testing. I suppose the Accelero S1 with a 120mm fan will be similarly successful on my 5850 once it gets here.
The HX520 is next to the ground in the P182

And there's hardly anything more quiet. There's the Seasonic S12 (the first model) and an Enermax MODU82+ that are arguably a bit quieter. However both of them were unavailable when I was setting up my computer, unfortunately. I went with the next best thing and I'm happy. There's a distinct hum from the PSU, but it's a low frequency sound which most of my visitors can't hear anyway

Well, I can, but I got used to it. There's also a Nexus 430W PSU which is by far the most quiet one available on the market (based on SPCR which I trust completely) - this one's 430W though and it was pushing it for a HD4870 when I was still running it.
As far as temps go, I didn't mind them (I put my legs on the case usually and it kept my feet warm

) - it was within ATi specs so why would I worry my head about it. But the speed-ups due to the high temp and very low basic RPM of the cooler really killed my silence-efforts. The Twin Turbo hardly helped with the noise (as in I could clearly hear it over the Nexus hum). Was thinking about the Accelero with a Nexus but then I got my PC gaming crisis and went with an Xbox

Bought a passive HD4350 and I'm happy

Maybe I'll get me a HD5870, need to see how quiet it is though (gogo SPCR!

). Btw. the Xbox gives me a headache after an hour... it's like a jet engine, seriously. Pump a stock HD4870 fan to like 80% and you know what an Xbox sounds...

Thinking about modding the PoS stock case to a LianLi XB01...

But the RROD warranty... decisions, decisions
Originally posted by: SSChevy2001:
The GDDR5 on the 4870 and 4890 downclocks just fine. Heck even the voltage can be dropped in the 0.95v to match the 5800 series.
Currently my 4870 idles at 157/200 mhz @ 0.95v with low 40C temp.
I did downclock my HD4870 to 160/225

I was getting flickering when the card was going into UVD or 3D mode. I had to perma-downclock the card to get rid of the flickering - temps went down to 38C idle with a Accelero TT at lowest setting. Couldn't game on it anyway with those settings. I tried many things to keep it low on idle and ramp up at load with no flickering - it just wouldn't work. I got my card on launch day. ATi didn't implement downclocking of RAM for a reason - it just wasn't working right, at least on the first batch of cards. After the aftermarket cooler I could still hear the HD4870 - bought the passive HD4350 to get rid of this problem entirely.
@OP: I'd wait for a comprehensive review by SPCR regarding the noise coming from a HD58xx card and then decide whether to buy it or not.