Build Advice Emptying the parts drawer and preliminary design review of a keyboard shelf mounted watercooled gaming system

Imacflier

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Jan 19, 2014
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Warning: This is a very long and detailed post, please bear with me.

Objective: A gaming system able to play AAA games at, as a minimum, 1440p and very high resolutions; physically located on my pull-out keyboard shelf; and, in so far as possible, making maximum use of parts from my parts drawer.

Background: My initial concept was to use the chassis and motherboard from an HP EliteDesk G5 Mini, an I9-9900KS, and an RTX 3070 8GB Vram, all parts I have on-hand. Based on discussions and information gained in a thread in CPUs, I finally decided that this was a high risk approach and I needed to do something with less risk.

When I was putting away all the parts I had pulled out, I noticed a dusty box in the very back of my parts drawer. I did not recall what might be in the box (that is what happens when one approaches 80 <sigh>). After I pulled it out, dusted it (and stopped sneezing!), I opened the box and found….Treasure! The box contained the parts I had gathered long ago for a planned MITX water cooled system which I never found the time to build.

The box contained (all new and inbox):
Conceptual Design: As I stared at this unanticipated collection of parts and recalled how much I had always desired a water cooled system, I had an ‘AHA moment’! Why not take all these parts, add appropriate power supplies and fans, lay them out flat like a giant breadboard, and mount them on my keyboard shelf? And so was born the Conceptual Design!

Preliminary Design:

Physical Constraints:
The layout is constrained by the physical space available on the pull-out keyboard shelf to 16 ¾” width x 12 ½” depth x 3 ¼” height.

Parts Selection and Rationale:

Main Processing Unit
: EliteDesk 800 G5 (Modified for Apogee Drive II clearance)
-Chosen for compactness, feature set, and availability
∙ 7” x 7” x 1 3/8”
∙ Robust I/O including USB-A, USB-3, USB-C, Thunderbolt 3 or 4, Ethernet, WiFi, and Bluetooth 5.0
∙ Socketed for LGA 1151 (I9-99xx cpus)
∙ Factory BIOS support for I9-99xx cpus
∙ Dual m.2 sockets: one needed for PCIe over m.2; one needed for NVME System Drive
∙ PWM fan control based on CPU temperatures
∙ Available as pullout from previous TVPC

CPU: I9-9900KS, this is the most powerful consumer CPU available for the LGA115x socket with 8 cores 16 threads, a base frequency of 4 GHz and an all core turbo boost frequency of 5 GHz.

Graphics Processing Unit: Gigabyte Rtx 3080 Extreme 10GB Vram Waterforce (a GPU with a factory mounted water block!)

Pulled from the magic treasure box!

Power Requirements and Solutions

CPU
: As much as 255 Watts during all core turbo boost.
∙ Solution: 330 Watt, 19.5 VDC Alienware AC adapter

GPU: 350 Watts without overclocking (unknown if overclocked)
∙ Solution: 12V 33A 400W Power Supply, AC 110-130V to DC 12V;
1.25” x 2.125” x 9.65”; Custom cable required

Cooling Requirements and Solution
It is difficult or impossible to sum the cooling requirements of each component, but it is safe to state that they cannot be greater than the sum of the power supplies. In this case 400 Watts of 12vdc + 330 Watts of 19.5vdc for a total of 730 watts.

∙ Solution: the Alphacool NexXxoS XT45 Full Copper 200mm Radiator (200mm x 45mm) has a cooling capacity of 720 Watts when paired with a 200mm fan. Once again sourced from the magic treasure box! This should be vastly in excess of actual need since if both PSUs are maxed out then something else is dreadfully wrong! If you are interested in how I determined the radiator capacity see: https://forums.tomshardware.com/thr...-loop-based-on-component-power-usage.3812337/ For a 200mm pcm fan I am trending to the Noctua NF-A20 PWM chromax, but am open to other suggestions.

Whew! Another interminable tome! If any of you managed to make it this far, thank you. And I earnestly solicit your opinions and advice, and promise to respond without rancor, but please remember the objective and constraints.

Next time and RSN (Real Soon Now) and assembly thread with pics!

Larry
 
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