Originally Posted by Cathar
I posted this at Procooling, but though it beared repearing here given the contents of this thread:
Seems that only half of the G7's mid-plate outlets are supported in the Swiftech version.
The mods weren't done so much to make a big difference on pressure drop, but rather for reasons of:
1) More rapid bleeding - air bubbles could get stuck for extended periods in the non-outlet end.
2) Impossible to assemble block incorrectly. Yes, had the odd person complain that their block was horribly restrictive, only to find that they had put the top-plate outlet above the blocked middle plate section. Can't happen now...
3) Improved stagnant water scavenging. While this doesn't affect the jetted area, the locations outside the jetted area, especially towards the blocked off side, could pool up water that just circulated around in a stagnant circle, rather than flowing out directly due to it needing to make a U-turn and head back to the exit, but fighting the outwash from the cups. So two localised eddies would form nearish to the cup area where stagnant water would just swirl about. This was observed by using clear plated (acrylic) prototypes and water dye. Also slower water would tend to accumulate towards the outer wall of the blocked end too. This is not so important though as it is quite a distance away from the main heat flux.
4) More even jet flow distribution. There was a natural tendency for the jets closer to the singular exit to receive a flow favoritism in comparison to the jets at the blocked end, just due to pressure drop across the inner plate jetted section. With the G7's 4 exit points, the water flow will much more evenly through the jets and away from the jetted region, with next to zero back-pressure affecting jet outwash.
5) Specific to the G7, it has a lower middle plate cavity height over the G4/G5, and so the entire middle plate surface outside of the jetted area now acts as more of a singular flat mini-channel. The G7 also includes turbulators hanging down from the middle plate ceiling to both increase middle plate flow speed and turbulence around the perimeter of the jetted area. This is to facilitate heat scavenging for IHS capped scenarios where even though the vast bulk of the heat flux is concentrated under the jetted area, the rest of the middle plate area works better at soaking up any residual heat flux towards the outer edges of an IHS.
6) Specific to the G7, the jetted area is ~35% larger on the G7, as opposed to the G4/G5, also to facilitate performance on abnormal IHS scenarios (flexible IHS's, non-flat IHS's, IHS's with non-uniform heat-flux between die and IHS).
7) Yes - marginally lower pressure drop. Not the main reason for the multiple exit points though.
Swiftech's Storm is making use of some of the above changes. I would've been happy to redo a proper Storm Rev2 for Swiftech using the concepts featured in the G7 had they engaged me to do so.
