Rack Mounted PC

[ncngrr]

Request advice on building a rack-mounted PC.

I plan to build a PC with the following specs:
- Asus P8Z77-V Pro (Intel Z77) SATA 6Gb/s USB 3.0
- Intel 3rd Gen Core i7 3770K (4.5GHz Overclock) Quad Core
- Antec 920 Dual Stage CPU Liquid Cooling
- 32GB Dual Channel DDR3 SDRAM 1866MHz
- 2GB Nvidia GeForce GTX 680, GDDR5, PCIe
- 950 Watt PC Power & Cooling MK II
- Creative Recon3D PCIe, 5.1 Channel HD Audio
- 512GB High Performance Solid State (SSD)
- 2TB WD Black Edition 7200 RPM, 6 GB/s, 64MB Cache
- Blu-ray (BD) Player DVD/CD Combo Drive
- 802.11n Wireless Desktop Network Card

I want to put this into a rack-mounted computer case.

So... I need help with the following:
1. How do I determine what size case is required (1U, 2U, 3U, 4U, 5U, ...)?
2. Once I determine case size, how do I know which cases are compatible with my selection of components?
3. How do I determine which case is best value given human factors (how easy/difficult it is to install components, how well the case supports cooling, etc)

I'm sure there's more I need to be asking, but having never built a computer before, I don't know what other questions to ask...

Thanks.

Scott

[zburns]

Quick comment right now!

One 'U' dimensionally, is 1.75 " (inches). You should use a rack mount case on the order of 4 U to 5 U high. This will allow for air flow that is in some 'degree' (likeness not temp!) comparable to an ATX vertical case. I have looked at the internet for 'builds' on RACK mount systems. Did not see any specific ATX build recommendations -- ie. no company promoting 'Rack' builds and (most important) providing instructions on 'how to do it'! It would not be a 'hard' or difficult build provided the 'builder' already has experience 'electronically' or is just plain good with 'common sense mechanical ability'.

Building or assembling with absolutely no experience is problematic to some degree. But 'new builders' who come to this forum are able to ask questions and read about other 'builds', etc.. This forum is one source of valid information for builders. In no way am I criticizing 'aspirations' of an individual wanting to do 'his first build' -- the point being it really helps the new builder if he (she) knows they are on 'familiar ground, ie. a forum like this or others, where comments on 'builds' and 'how to' are commonplace --
that said, a 'rack mount' build is not familiar, in general, to these forums. So comments from direct hands on experienced personnel may be limited.

The main difference between a 'routine ATX cabinet or case build' and a Rack mount build is the thickness of the case or cabinet with respect to air flow. An ATX vertical case width of about 8 inches is apx equivalent to 4.6 'U' so to best 'mimic' ATX flow the Rack build should be 4U (7") or 5U (8.75") in height (thickness). 5U more closely approximates routine ATX vertical cases. Once more the reason for the 'thickness' is to allow for 'reasonable air flow' -- as compared to a thin case with 'air turbulence of some degree'. It may be very difficult to build a Rack Mount computer that mimics a desktop (component wise) if the thickness is 2U ( 3.5 inches) -- once you get the build complete (with no available instructions) you will have to test for temperatures. If they are too hot, the only solution may be to increase from 2U to 4U or 5U. The only way to test for temperatures is to use multiple 'thermocouples' with an appropriate electronic readout

Whether the main 'air flow' in the (total vertical RACK) is mostly vertical or mostly horizontal is another factor. Racks can contain exhaust fans at the top to force air flow to be essentially vertical; in which case the computer build would have to have many ventilation holes in the bottom frame of the computer rack; the motherboard would have to be mounted horizontally because of its size (I read in several places that most rack mounts use 'micro ATX' motherboards -- which have limitations). A vertical fan exhaust system used for 'cooling' a 9 X 12 inch ATX motherboard that is flat and horizontal with respect to the air flow is problematic at best. Vertical air flow for the whole rack is 'interfered with' because of the 'flat motherboard size'.

Vertical ATX case dimensions meet requirements of the 'ATX standard for cases' -- an industry wide group of 'desktop computer component suppliers'!

The major problem in doing a rack build with an ATX mobo is the air flow and cooling. Another problem is knowing the 'idiosyncracies' of the builds end result since it is likely no one has direct experience in doing such a build.
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I am not saying 'do not do this' -- just pointing out that there are more challenges than in the 'builds' we see on this forum.

[zburns]

Answers to these questions:
1.
How do I determine what size case is required (1U, 2U, 3U, 4U, 5U, ...)?

3U would be a height of 5.25 inches and probably too small; reasoning being more height space to minimize air flow turbulence. 4U is 7 inches thick (height) and probably could be made to work. 5U is 8.75 inches in height and would surely be more than enough clearance to minimize turbulence.

You need to find a RACK manufacturer or supplier who has experience with a rack mounted pc, and, in fact, supplies and, or, manufacturers a RACK mount 'module' designed specifically for ATX components. There are probably some such manufacturers who can provide the rack mount cabinet; finding a manufacturer who can supply a cabinet that meets ATX specs may be more difficult. As long as you can find a Rack Mount, say 4U or 5U in height, designed to meet ATX component specs, you can probably make it work.

2.
Once I determine case size, how do I know which cases are compatible with my selection of components?

Answered as part of first question, meaning designed specifically for ATX .

3.
How do I determine which case is best value given human factors (how easy/difficult it is to install components, how well the case supports cooling, etc)

A dilemma here regards 'knowledge of sufficient cooling'. Unless you can find a suppler who has hands on experience or customers who have specifically built ATX computers within a RACK Mount enclosure, you will not have an answer regards how well the case supports cooling.

Conclusion: Rack cabinets in industrial and research sites are bound to have 'sections' within a Rack Cabinet that are devoted to the equivalent of a ATX desktop computer. The challenges are the cooling. The motherboard is large (about 10" by 12" worst case) and you have to consider the PCIE slots and what goes in them. My point in this conclusion is that 'surely a desktop configuration' can be installed in a Rack Mounted configuration, but the so called cabinet must be different in configuration than the desktop; I would conclude that there have to be manufacturers out there who have done this using ATX components. There has to be enough space to do it and get good air flow; estimate about 7 to 8 inches height, which is a generous space.

There may or may not be 'do it yourself instructions on how to do such a build'; should be able to find something on the internet with an organized 'look' ! !
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Here is one manufacturer similar to what I refer to above: http://www.stealth.com/industrial_rackmounts_4U.htm this url takes you to a specific 4U RackMount ATX computer by 'Stealth.com'

This url: http://www.stealth.com/industrial_rackmounts_ALL.htm This url is the same manufacturer except this url takes you to a long page of a number of different size Rack Mount ATX computers.

The company Stealth.Com appears to be a company that builds these Rack Computers 'for sale' -- it was easy to find this. Just proves that Rack Mount computers are available. Also means that a 'builder' can buy a case and install ATX components, etc. to do his own build.