Kraken Z73 - Push/Pull?

Nitefly

Nitefly

Nitefly

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Worth it?

Can get a single straight answer from searching so thought I’d ask here :o

For completeness I’m going to get a Lian Li XL case a bunch of their SL120 fans. 3x intake at the bottom, 3x exhaust at the top, a bonus exhaust at the rear and then, in the front side panel thing, the radiation with 3 or 6 more fans depending on whether push/pull is worth it.

There is only ~£70 cost different.

More fans more noise... but more fans lower RPM so less noise....

Blergh.

Cheers! :)
 
Very little difference with push pull mate I've done it and found it a waste of time,save the money and spend elsewhere.
 
What clone said.

Keep in mind you need at least as much exhaust vent area (with or without fans) as you have intake fans for intakes to have optimal flow.
If you have less exhaust vent area it will limit total case airflow to how much air can flow out exhaust vents.
For air to be flowing into case air the same amount of air has to be flowing out.
Maximum case airflow is the lesser of the two.
So if exhaust has less flow area than intake, case can only flow that lower amount.

Which may be fine, but you will likely have same flow with less intake fans.
I've also found having both intake and exhaust fans is rarely needed. It's like having push/pull fans on a radiator .. little to no improvement, but more noise.
 
Thanks both.

@doyll - with there being more intake than exhaust, to my mind (without being an engineer) I had anticipated that this will result in air pressure pushing air out of the case through cracks and other gaps as the ‘worst case scenario’, which then helps avoids hot air blowing back into the case. There’s some other air grills where the air can pass through (other than areas where the fans are).

I know what you are saying though. It’ll be a 6 fan intake vs 4 fan exhaust - hopefully not too problematic!
 
It will. Just wanted you to know that 6x intake fans and 4x exhaust vents will not give you 6x vents of airflow. It is only 4x vents and whatever leaks. A good part of reason I quite using exhaust fans was not just less money being spent and just as good case airflow and cooling, but also because theres no worrying about dust leaking in (except maybe PCIe slots closest to GPU fan if case intakes are not flowing enough air in). I just set case fans to be flowing a little more air than components are using and all is good.
 
As mentioned above, you will see a minimal performance increase going push-pull on a 30mm rad. That's more for the 45 and 60mm ones.
However, it could be as much as 5ºC, so potentially worth it... You be the judge.

I would suggest turning the bottom over to exhaust, though, as that will draw less dust in.
 
doyll said:
It will. Just wanted you to know that 6x intake fans and 4x exhaust vents will not give you 6x vents of airflow. It is only 4x vents and whatever leaks. A good part of reason I quite using exhaust fans was not just less money being spent and just as good case airflow and cooling, but also because theres no worrying about dust leaking in (except maybe PCIe slots closest to GPU fan if case intakes are not flowing enough air in). I just set case fans to be flowing a little more air than components are using and all is good.
Click to expand...

Ah re-reading your first post I see what you mean.

There is effectively the equivalent of 5 exhaust vents in the case (of which 4 will be covered with fans), so better than merely 4 exhaust vents. If you look up the case I’m referring to you’ll see the back of the case has lots of places for air to escape.

Cheers for the input! Went with 10 fans in total and won’t be doing push/pull.
 
ttaskmaster said:
As mentioned above, you will see a minimal performance increase going push-pull on a 30mm rad. That's more for the 45 and 60mm ones.
However, it could be as much as 5ºC, so potentially worth it... You be the judge.

I would suggest turning the bottom over to exhaust, though, as that will draw less dust in.
Click to expand...
This goes against my natural instinct of ‘heat rises’ but I guess it’s all much of a muchness! Is it particularly superior re: dust? The PC will be on my desk rather than the floor.
 
Nitefly said:
This goes against my natural instinct of ‘heat rises’ but I guess it’s all much of a muchness!
Click to expand...
Heat does NOT rise.
If you don't believe me, hold a 6" metal strip by one end and point the other end directly up. Then stick a blowtorch flame on the top end, and wait for a few minutes... Remember to wear a Covid mask when you go to A&E for burnt fingers! :p

Warmer air will rise (which is why it's called a 'hot air' balloon), but your PC fans have enough power to easily overcome this.
Again, put the kitchen hob on low and hold your hand about a foot above the burner. Power up a PC fan and direct the air to flow sideways just below your hand. ;)

Nitefly said:
Is it particularly superior re: dust? The PC will be on my desk rather than the floor.
Click to expand...
If your PC is on any surface, dust will gather more on that surface and then be drawn in by the airflow. The surface sort-of helps to funnel the dust.
Having fans exhausting out the bottom is superior... The measure of how superior depends on all the usual factors and particulars of your build, but I always find less dust than having no fans there at all, and far less dust than having fans as intakes.
My PC is also on my desk top, but I still get some dust inside. I just get a lot less than if I was intaking from below.
 
push and pull improves air flow into the case if it is used on rads as intakes and you can run at lower RPM thus less noisy even on thin rads.

on thicker rads, there will be a bit of difference
 
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