[8-Ball]

Superart, I'm not sure you are listening.

You will have lower flow through the cpu block and the gpu block in the setup you have described than if the whole lot were plumbed in series.

Also, please take note of the point I made about the water not really heating up as it goes round the loop. If it's flowing relatively quickly, it will only be heated by around 1 degree by going through the blocks.

Let me put another argument to you.

Most of the pumps used in watercooling are not really ideally suited to the job.

An ideal pump for watercooling, would have a lower rated max flow rate than the eheim 1250 for example, but would be capable of producing a much greater pressure.

Since we are operating at the high pressure, low flow rate end of the operating range of most pumps, the L20 included, we would gain significant benefits in flow by increasing the pressure produced by the pump rather than the freeflow rating.

Pumps in series increase the overall pressure produced by the pumps, while pumps in parallel increase the freeflow rating (pretty useless).

I know it would seem that separate loops would be the best way to go, but this question has been asked MANY times before and serial is the way to go, particularly through the cpu block. Some benefits can be gained by running the gpu and northbridge blocks in parallel, but only after all of the water has been through the cpu block.

I would wager that the flow rate through the cpu block in the diagram you have drawn would be lower than the flow rate for the whole system in series with just one of the pumps.

And what happens if one of the pumps fails?

Some of the water will now flow backwards throught the other pump. Is this bad? Yes, because not all of the water will be going through the rad.

What about in series?

If one of the pumps fails with them in series, it doesn't really matter, you will still have pretty adequate cooling for as long as it takes to replace the failed pump.

Does that make sense?

8-ball