H20-APEX setup with GPU block

[gilden_man]

Hi,
New to water cooling, but I've been reading for a while.
I'm planning on getting a Swiftech H20-APEX kit, but I also wanted to add GPU and chipset cooling to it. I was thinking of Swiftech's new MCW55 GPU block and MCW20 chipset block. I notice they have discontinued their MCW20 tho. Is this due to the NB really not warranting water cooling?
I'm wondering how best to put these 3 (or 2) blocks together. The Swiftech APEX docs show the setup as radiator, CPU, reservoir, pump; which makes sense as the CPU gets the coolest water. However, adding the GPU and chipset cooler adds some extra combinations of connections of which I'm not sure which is the better:

1. Everything in series. radiator, CPU, GPU, chipset then reservoir?

2. Y splitter after radiator; 1st line to the CPU only, returning into 1 of the 2 reservoir returns; 2nd line from splitter to GPU and then chipset returning to the other reservoir return.

I'd assume the 2nd is best, as isn't the 2nd reservoir inlet specifically there to allow this configuration to reduce pressure drop on these more complex configurations?
Now there is which tubing to use. The H20-APEX kit uses 7/16" ID, 5/8" OD for reasons best described by Swiftech:

"The 7/16" ID tubing features the same or better flexibility than 3/8" ID tubing, no distinguishable difference in terms of system flow rate compared to 1/2" ID tubing, but significantly reduces the bulk associated with 1/2" ID thick wall tubing."

I assume then that they are squeezing this 7/16" ID tubing onto standard 1/2" barbs as they make no mention of the support of 7/16" barbs anywhere on their website.
However, the MCW55 GPU block and the MCW20 chipset block both have 3/8" ID quick connectors. This gives further combinations for the 2nd line:

3. Use one 1/2" ID hose barb adaptor for the inlet the GPU block and then using 3/8" ID tube all the way back to the 2nd reservoir return.

4. Using four 1/2" hose barb connectors (2 for GPU and 2 for chipset block) to enable the use of the same 7/16" ID tubing for the whole 2nd line.

Option 4 means slightly more liquid is in the system. But will this also help the flow into blocks constrained by 3/8" ID inlets?

So which of the 4 options would be best together and do I really need a chipset cooler?
Many thanks for any of your experience here.

BTW This is on an Abit NF7-S with XP-M 2600+ overclocked to 10.5x235 2.468GHz and an Antec Sonata 1 case.

[billbartuska]

Option1 is best, actually it is the only one that will work corectly. Use the largest hose you can get into your case.

[gilden_man]

Originally Posted by billbartuska

Option1 is best, actually it is the only one that will work corectly. Use the largest hose you can get into your case.

So it's better to stick with 1/2" ID tube throughout and use 1/2" barbs on everything that only has 3/8" connectors?
You don't see the GPU and chipset blocks only having 3/8" ID connectors as a problem?
The Swiftech MCRES-525 two inlet reservoir is fundamentally flawed then?
Cheers.