CPU heatsink fan advice (megahalems)

dennisresevfan

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I'm about to get myself a Core i7 processor, along with a Megahalems Rev B heatsink to keep it cool.

I need to choose what fan(s) to use with it.

I'm currently thinking of using two Scythe Slipstream 1900rpm fans in a push/pull arrangement. They give 110CFM for 37dbA, which is impressive, but possibly a little loud. Good for £10 or so per fan though!

How loud is that really? I tried using a fan noise comparison site, and it doesn't seem too bad, but of course it's hard to know what to set my volume control to!

I also found this: http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=4675263&csid=ITD&body=MAIN#detailspecs

19 dBA and 90 CFM.

Looks to be very good CFM for that noise rating. But I can't seem to find that fan anywhere to buy in the UK!

I've heard good things about the "Noiseblocker" fans. But their website is in german and once again I'm not sure where to source the fans from in the UK.

If anyone speaks german and/or knows where I can get those fans, please feel free to suggest one that I should get.

I'm planning on overclocking the i7 930, so I do want good airflow through that heatsink. I don't want a fan that would annoyingly loud though.

So I'd appreciate some advice on how many dbA is too loud (two fans at that dbA rating).

And also about what specific fan would be good to get.
 

dennisresevfan

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I'm about to get myself a Core i7 processor, along with a Megahalems Rev B heatsink to keep it cool.

I need to choose what fan(s) to use with it.

I'm currently thinking of using two Scythe Slipstream 1900rpm fans in a push/pull arrangement. They give 110CFM for 37dbA, which is impressive, but possibly a little loud. Good for £10 or so per fan though!

How loud is that really? I tried using a fan noise comparison site, and it doesn't seem too bad, but of course it's hard to know what to set my volume control to!

I also found this: http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=4675263&csid=ITD&body=MAIN#detailspecs

19 dBA and 90 CFM.

Looks to be very good CFM for that noise rating. But I can't seem to find that fan anywhere to buy in the UK!

I've heard good things about the "Noiseblocker" fans. But their website is in german and once again I'm not sure where to source the fans from in the UK.

If anyone speaks german and/or knows where I can get those fans, please feel free to suggest one that I should get.

EDIT: I've had a look through what I CAN read and honestly I'm not too impressed. Sure they're quiet, but the CFM rating sucks (after conversion from their units)

I'm planning on overclocking the i7 930, so I do want good airflow through that heatsink. I don't want a fan that would annoyingly loud though.

So I'd appreciate some advice on how many dbA is too loud (two fans at that dbA rating).

And also about what specific fan would be good to get.

They must be 120mm to fit on the Megahalems, I believe. Correct me if I'm wrong. Anyway, I'm pretty sure anything larger would block my ram slots.
 
37dba for 2 fans is about as quiet as your gonna get. The 90 Cfm fan looks great if you can find it but running that scythe 37dba is at full speed so for the most part you wont be running it that fast.
 

dennisresevfan

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It's 37dbA for EACH fan.

Here's a thought. The Scythe Slipstream has a 3 pin connector. I believe my case's fan speed controller has a 3 pin connector.

Should I use that? Or am I better off using the motherboard connectors for PWM fan control?

For some reason my speed controller doesn't seem to be working at the moment though it used to. Maybe someone at the pc repair shop didn't fully wire it up. Still, there's a chance it's not working. (It's showing the fan speed but I can't change it)
 

LePhuronn

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Noiseblocker fans are available from overclockers.co.uk

I'm going with Akasa Apache Black PWMs on my True Black Rev C (or Mega Shadow - not decided), but anything with high static pressure would be good on the Megahalems/Mega Shadow.

Scythe Gentle Typhoons are apparently good on radiators, so they should work nicely on the Megahalems too.
 

dennisresevfan

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Hmm. The Gentle Typhoons aren't bad, but the CFM rating is a bit low. 57CFM for the 1850rpm version.

Same issue with the Akasa although the rpm on that is lower.

Then again, I don't really know how much difference CFM is going to make.

Would you say 37dbA is irritatingly loud? I might be able to use a fan speed controller, so it may not be a problem.
 

LePhuronn

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dennisresevfan

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Nah, but I don't think I could have gotten away with tall heatspreaders anyway. Even a 25mm fan might be a problem with that heatsink. So I already planned on getting low profile OCZ "Gold" ram. The heatspreaders are on the sides of the ram sticks.

http://www.thecoolingshop.com/product/SilenX-Ixtrema-Pro-IXP-76-18-18dBA-120mm-x-38mm-Quiet-Fan_26354.html

Yep, and I just found that one myself. For the first time ever, google shopping search actually worked.

When I tried actual google and various searched on amazon etc, it kept finding other less useful models of fan from the same company.

Seems to be a pretty awesome fan.

So unless anyone thinks they can beat that... I think I'll be getting those.
 

dennisresevfan

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Hmm. I've found some rather worrying reviews and youtube clips about these fans.

Basically it seems that some people are delighted and others think they totally suck. It's pretty confusing.

http://www.frozencpu.com/products/4274/fan-235/SilenX_120x120x38mm_-_18dBA_-_90CFM_iXtrema_Pro_Fan_with_Fluid_Dynamic_Bearings_IXP-76-18.html

http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16835226013&Pagesize=100&Page=1

http://www.youtube.com/watch?v=zPtqgKytf2s&feature=related

http://www.youtube.com/watch?v=GmyL3SoYtag&feature=related

Very strange. Some reviews are very positive and some are very negative. One youtube clip has the fan practically being silent. The other... well, it's clattering like a misfiring Model T ford.

Should I be worried? Or is this just a case of some fans being crap, and needing returning for a replacement?
 

LePhuronn

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it's your call

if you think these fans are worth the potential grief of getting dead ones and returning them then go for it.

personally i'd look at something else with a failure rate as high as these seem to have.
 

dennisresevfan

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Is there by any chance a site with information about the best fans for use on a large CPU heatsink? I keep hearing about static pressure but I have no idea what fans are best for static pressure...
 

HeroicHero

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Is there by any chance a site with information about the best fans for use on a large CPU heatsink? I keep hearing about static pressure but I have no idea what fans are best for static pressure...

Basically, it's the ability to keep up the desired airflow even with the obstructions in the fans path. (in this case, the heatsink) Since fans mounted on heatsinks have a lot of substance in their paths, it's best to use a fan with good static pressure.
 

dennisresevfan

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Hmm. I find myself being drawn back to the Slip Streams. They're probably fine when used with a speed controller. I just hope mine isn't busted or something. Doesn't seem to be changing my fan speed at the moment.

The Slip Streams apparantly have a predicted lifetime of 3 years, which isn't so bad, but it's nothing compared to a lot of other fans I've seen. The performance on the others usually sucks though.
 

dennisresevfan

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Yeah, but I can't find out which fans actually DO have good static pressure. It is unbelievably annoying.

Apparantly the Slipstream static pressure sucks though, so it looks like that fan would only be good as a "pull" fan on the other side of the heatsink, if anything.

I left Scythe an email asking them to recommend a fan. Let's see what they claim is best.

But does anyone have a suggestion in the meantime? Forget about CFM. It's performance with a dense heatsink that I'm interested in at the moment. High static pressure ability. Preferably with low noise.
 

LePhuronn

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Usually the more blades on a fan the higher the pressure from what I've seen - most 120mm fans are 7 blades, so look for something with more than that.

Scythe Ultra Kaze, Noctua, Akasa Apache, that sort of thing.

Also 38mm fans tend to have higher pressure because of the extra thickness - gets more air going and reduces the dead spot around the centre of the fan. This is why a lot of hardcore cooling peeps talk about using shrouds on fans to move the actual air generation away from the heatsink or radiator enough to allow more airflow and remove dead spots.
 

dennisresevfan

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Hmm.

Well, I keep hearing good things about Noctua. I left them a filled out contact form asking for a product recommendation.

One possible problem is that I'm not sure if I'll have space on the other side of the Megahalems for a "pull" fan. I guess I'll just get one fan and attach another one later if it's possible.

Then again how much does a "pull" fan really help?

I've got an old fan at the front of my PC case which isn't really pulling any air in (lcd front panel blocking it). I could just use that if there's space... Actually, removing that would help with my power cable management too.
 

dennisresevfan

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Seems some of the website is in english. I'm not sure why but one product range is in english and the other is in german.

Nothing I could find in english looked all that wonderful to me, I must say.
 

dennisresevfan

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What do you personally make of Noctua? I keep hearing good things about them but I've not seen any actual figures for static pressure. They do seem to have a reputation for providing a good value for it though.