# How many cube inputs are needed for stable Matrix Lab work in DSP?

I just noticed that at max lab vertical construction levels, which is 15, there's not sufficient white cube input and always 4 or 5 levels are lacking matrix. So how much inputs should I enter into this lab tower, knowing that the current number of 4 white cube inputs are not enough?

EDIT: There's been an update to the game which has the potential to drastically change things by piling inputs. As a rule of thumb this maximizes out at a pile four high, which means that the carry capacity for a belt quadruples if you can keep them coming at that rate. I'm not at that point yet myself, but my guess is that this will skew it significantly in favour of the sorter, which can now grab its maximum capacity and pull it in much quicker, meaning less turnover time, meaning more trips per second.

TL;DR: Do the math.

All the following values assume infinite supply; obviously if you're producing them slower than that, there's your bottleneck.

Look at a single research lab. Unfortunately, the game doesn't tell you the exact amount of time it takes to process a cube (and that is going to depend on how many upgrades you've researched), but looking at my own stack and keeping a stopwatch to hand it processes 10 cubes in about thirty seconds - so three seconds per cube, so 1/3 cube per second.

UPDATE: You can get some hard numbers by looking at your production screen:

I've got two full stacks and at maximum activity they consume a total of 1200 cubes per minute, or 20 per second, so 10 per second per stack or 2/3 of a cube per second per individual lab.

A single T3 belt can supply 30 units per second; a fully upgraded T3 sorter traverses 6 grid units per second with a stack of six. Counting round trips, that means that a belt right alongside the lab can get served three times per second (one grid unit either way, 6/2=3), meaning a single sorter can supply 18 cubes per second to your lab stack.

What this means is that a single T3 belt can precisely supply three full lab stacks, and if the belt is directly adjacent to the stack a single max-upgraded T3 sorter can easily keep a single stack supplied.

I'll try and do a couple of research upgrades tomorrow or this weekend and see if that alters the equations significantly.

Conclusion: Assuming sufficient supply, a single fully upgraded sorter is perfectly capable of keeping up with the demands of a maximum height lab stack. If you're really having trouble and it's not because you've got a cube deficit, consider upgrading your sorter cargo stacking capability to max (not a bad idea in any event because it will help with everything).

Evidence:

Both of those towers are running on full stacks with a single sorter per tower, and they're doing fine and have been doing for several thousand cubes.

• Interesting, I calculated the same amounts of cubes per second for fully upgraded belts and sorters. Even spamming them from MK2 max level storages and still the last 4-5 levels are lacking the white cubes. Dunno why ... Commented Aug 31, 2021 at 16:24
• Is your belt right next to the tower? Commented Aug 31, 2021 at 18:19
• I'm not sure what is going on in that screenshot you've posted. May I recommend, just as a precaution and to eliminate confusion, to set up a new processing/research center where each research tower is fed by a belt coming directly from a planetary logistics station and seeing how that works out? Commented Sep 1, 2021 at 9:43
• TODO, T3 Belt capacity with Automatic Piler stacks (four items tall). Commented Jan 28, 2022 at 14:48
• @amyb I started an entirely new playthrough and I'm still working on pilers. If you'd like to edit in some hard numbers for the update, feel free. :) Commented Jan 28, 2022 at 16:48