In this post you attached a photo of you system. I have added in an edit. You should mount fans on the sizes indicated in spots indicated. Don't use Dall fans, use something else and use your adapter cable you made.
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Make sure you have them pointed with the airflow moving to the rear/out of the case. This will improve cooling greatly.
Yeah don't worry I had this idea I just struggled to find a clean way to attach a small fan I had that almost fit to the aluminium tower and didnt want to use the glue gun for that.
The plastic cover also doesn't help.
And then I found my old fan from a dead dell optiplex that fits perfectly at the back so I installed it.
Actually if I put my hand behind the case while it's utilizing the GPU at 100%, the air is super hot so it does it's job but I would like to see it spin faster when it has to. My CPU stays below 70° anyways so I'm not too concerned about him but about the overall temperature of the RTX 2060 Super (83°)
Someone talked about the temperature sensor for the hdd, I'm not really aware how that works but maybe it's the solution.
My NVMe SSD (green light you can see on the picture) will inevitably get hot if the gpu spits hot air in the case so maybe that would force this back fan to actually spin fast and then fix the problem.
Also it's a small fan, smaller than the regular 12mm ones,a real 12 mm blocks the closure of the case.
The T5810 features two airshrouds over the memory banks as standard. These may help, too.
Then there is (a header for) a temperature sensor.
Normally intended to measure the harddrives temperature, placed near the gpu´s exhaust one maybe can alter at least the speed of the front case fans (+ auxiliary fan? I think this one is fixed speed only.)
Shrouds and temperature sensor are expensive parts compared to the price of a used Precision WS.
Ah I removed the shrouds because I inserted the back fan.
The shroud was supposed to be inserted at the place I have the fan (left one) and the other one would force me to remove the fan header.
I don't think it's too important, afaik it's supposed to cool the ram which is not getting too hot anyways.
This fan looks quite weak but if I put my hand just behind his exhaust it's really hot and it helps the case stay cool, it's just not enough, but better than before.
