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Cooling with Six fans and variations on traditional cooling

Cooling with Six Fans

Dialling things up to max and filling all the fan mounts (apart from the troublesome Roof (F) mount) gives, predictably, the best results we’ve seen so far. As you can probably guess though, the advantages of adding a sixth fan are minor to say the least - the CPU and GPU and chipset delta Ts dropped by only a single degree. This is a fairly measly improvement over the already excellent cooling offered by a five fan setup.

Things can also be put into perspective by pointing out that the respective CPU and GPU delta Ts of 43oC and 45oC are only a couple of degrees better than was achieved with four fans strapped to the case. This is a fairly damning result as not only will the extra pair of fans set you back the best part of 20 notes but they’ll also create more noise, both mechanically and through in-case turbulence.

Six Fans

Arranged by CPU Delta T

  • Front (U), Front (L), Rear, Roof (B), Side, Floor (All Fans installed)
    • 43
    • 45
    • 17
0
10
20
30
40
50
°C, lower is better
  • CPU
  • GPU
  • Chipset

This was a pretty flat and uninspiring end to our testing so, frankly, we decided to have a little fun and see if we could revolutionise the world of PC air cooling by experimenting with some alternate cooling arrangements.

Alternate Cooling Arrangements

First on the list, for some reason, was orienting all six of the attached fans so they were acting as intakes. Obviously this is slightly ridiculous set up and it proved to be utterly useless at cooling too (who’d have thought?). This was largely because the rear and roof (B) intakes were both pushing against the fan on the CPU cooler. We remedied this by flipping the CPU cooler round so it was now pushing and this had an immediate effect on the results, dropping the CPU delta T down to an actually rather good 43oC.

Unfortunately the GPU spoilt the party as it didn’t like this setup very much at all as the hot air from the CPU cooler was now being blown back at it by the two front intake fans. Back to the drawing board we guess.

Next up we flipped all the fans over so that we were running with six exhausts. This may sound mad, but we’ve already established that, all other things being equal, you’re better off getting heat out of the case than pushing cool air in - surely having all the fans as exhausts must be awesome then? Well…no.

Cooling Variations

Arranged by CPU Delta T

  • Back to Front cooling
  • All Intakes - CPU to Front
  • All Exhaust - CPU to Rear
  • All Exhaust - CPU to Front
  • All Intakes - CPU to Rear
    • 40
    • 50
    • 19
    • 43
    • 51
    • 21
    • 46
    • 50
    • 27
    • 46
    • 54
    • 30
    • 49
    • 52
    • 21
0
10
20
30
40
50
60
°C, lower is better
  • CPU
  • GPU
  • Chipset

In fact the delta temperatures we saw with this arrangement were, if anything, worse than those we saw with all the fans acting as intakes. The GPU in particular got very toasty as it was being completely starved of air by the side and floor fans.

Last on our list of cooling adventures was seeing if we could turn the world of air cooling on its head by - wait for it - in taking air from the rear and exhausting it out the front. To do this we reversed all the fans in the case from what would be their traditional role. Dramatic we know, but not ridiculous - the CPU is located near the rear of the case after all, surely it’d like this arrangement.

Sure enough it did (we reversed the fan on it again so it was pulling air from the rear of the case) and we saw our lowest CPU delta T with this arrangement - a full 36oC less than our first reading taken with nothing but the CPU cooler and all the fan mounts blanked up. Again though the GPU kicked up a fuss with the fans arranged in this way - not a massive one mind - but it clearly wasn’t suited to being cooled in this way as it had no dedicated intake fan.