Order of Assembly

Hey guys, hopefully I'll be getting the parts for my first 100% home built system coming through this weekend, so I figured now's a good time to check some of the small detail on how to fit the whole thing together :)

1) Is it worth doing a test build outside of the case, grounded on some thick cardboard or similar? If so, how fiddly does it get to screw a fully loaded motherboard into a case.

2) Does it make a huge difference whether the fans are wired up direct to the PSU or attached to the motherboard?

3) Front panel audio, how do I find out which cables correspond to which motherboard headers, it's one thing I never got working when I was helping with my mates PC build.


Any other tips?

1) I have sausage fingers so I always install cpu, cooler (fan connected to mobo) and RAM whilst the motherboard is out of the case simply because it's easier. I usually use a piece of cardboard then put that foamy stuff that comes with mobos on top then the mobo. Makes it easy to turn around and work on.

A test build is not a bad idea. Saves putting it in the case then finding problems. It's not fiddly to put mobo with cpu,cooler and ram into a case.

2) Dunno never tried it with psu, but I always connect cpu fan to mobo.

3) Your manual will give you a diagram of the front panel audio pins. The case front panel cables should then have markings on them that match up. eg. HDD LED, PWR SW, PWR LED + and -, SPK, RESET etc USB/Firewire tend to go somewhere else on the board.

Normally if the on light on the front of the case does not light up then the PWR LED cables needs to be swapped around.

I wish the industry could agree on a standard front panel config so we just had to plug in one lead. Big fingers, small cables and positioning the FP connector in the far right of the mobo leads me to frustration!

Tip. Try to be patient and take your time.

I also put memory/cpu/cpufan before I put in case but i do it because sometimes a little force is required to attach the fan.
As for testing i always put in case unless im just testing the mobo

The pins are not always labled the same as the manual though :(
when you get the pins right you can put i bit of tape arround them so if removed they
are easyer to replace
I hardley ever use the front panel audio so i dont have a problem with leaving it off for personal PC's
Some cases have blocks of pins as well as single pins so they are easy

fans attached to mobo can be monitored/speed adjusted ( depending on fan type and mobo ) if i can i attach to mobo if not then psu

A lot depends on the layout and size of the case. Mounting all the components on the mobo before installing it in the case is easier, but it makes the board slightly heavier to handle and if the it is a tight fit in the case there is the slight risk of damage when you are installing it. However if the case has a removeable motherboard mounting plate, that is probably the best way.

The CPU heatsink is probably the hardest part to fit, the clips are usually quite strong and can require quite a bit of force to locate them. Doing that in a small case can be fiddly. Installing memory after the mobo is installed is usually straightforward - but again depends on the mobo layout and case size.

As for the PSU - I usually install that in the case first - but then the wires can get in the way - but installing the PSU afterwards can be tricky if the mobo gets in the way.

So really - it all depends on the specific components you are using.

Of course, if you build it first outside the case to test it, it makes no sense at all to dismantle it (apart from any pci pci-e cards) to install it.

So take a some time thinking about how the components will fit together, and take your time doing it. The mobo layout and connections will be described in the mobo manual.

I tend to put the CPU/HSF and RAM in outside the case and the PSU and drives inside the case, then fit the mobo (removable tray makes this easier, and a tight case may even prevent this with a large HSF), then add any cards. I don't test it outside the case, because the only thing that would do is prevent shorting, which actually is a very rare occurrence if you don't do something stupid like drop a screw under the mobo. It might not be a bad idea however if the case doesn't have a lot of room, as it might be a pain to dismantle. This is why roomy cases are popular!

And yes the worst part of a build is all those fiddly Power & LED headers and I wish they'd sort these out - sometimes the Power LED header from the case doesn't even match the mobo (2 vs 3 pin).

I would also go with the get the cpu cooler and ram seated outside the case, then get PSU and drives sorted inside then get MB in place.

This all works on the assumption that your case doesnt have any quirks which will prevent the MB going in after the PSU for example.

With my Silverstone TJ-08 with a Thermalright Ultra 90 cooling my CPU I need to remove the PSU to get the removable motherboard tray out... my fault for getting a tall-ish cooler :)

Just make sure you put the I/O EMI shield in first!

When it all doesn't work, and just after you finish panicking that you've FUBARd something, do one final check on the rocker switch on the PSU.

That should save you completely stripping everything out and starting again, and in turn wasting a lot of time

Thanks for the advice.

Hopefully it won't be too bad to sort out, no removeable motherboard tray (case is a Lian Li PC-A05) but it's got a nice open space for the motherboard since the PSU is mounted at the front of the tower.


For the front (well top) panel, I'll just have to guess with the wiring as I dont think I got a manual for the case.

It's the manual for the motherboard that you actually need. The cables from the case should be relatively easy to figure out (and cases rarely seem to have manuals in my experience).