NZ Techonverse: How To Build A PC From $300 To $3000 [1]

First published on NZ Techonverse

One of the great strengths of the PC platform is the wide range of configurations which are possible from entry level to high end workstation, or server. PC based servers use the same basic and often interchangeable components as the lowest spec system you can buy. For the point of this discussion I’ll ignore single board systems like the Intel NUC or Compute card, which have embedded CPU, and go with the most basic level of system that has a CPU socket that enables you to have a choice.

I have personally built or maintained systems within various price points in this range. It’s getting a little harder in these days to build a $300 system because of price rises in the Covid era due to higher shipping costs, so I’ll do my best to illustrate the equivalent that might be possible today. These articles only cover the hardware. I use the free Linux operating system for nearly all of my hardware, but a system builder could choose to buy a Windows license if they wanted to use that OS.

The basic components of a PC are:

Chassis (case)Power supply. Mainboard (or motherboard as is more commonly used).CPU (microprocessor)RAM (main memory)Storage (disk)

The above are the parts that make up the chassis and its internal components (the basic “system box”). To these you will normally add a keyboard, mouse and display. You might also add some additional internal components, most commonly a card in a slot. The most basic systems don’t need any cards, since most desktop mainboards these days have integrated sound, graphics and networking capabilities. It is however relatively rare to incorporate WiFi or Bluetooth into a desktop form factor mainboard, these are more commonly found in laptops, or some compact forms such as the Raspberry Pi or Intel NUC.

The cheapest way of building a new computer is to be able to recycle components from old computers. For a PC, the components that can’t be recycled readily are the mainboard, CPU and RAM. This is to say that you can’t take an old mainboard and put a modern CPU or RAM into it. You can’t take an old CPU, or RAM, and put it into a new mainboard. These three components are the ones whose interfaces change the most frequently. RAM is the most reusable component of those three, and within each band of DDR, for example, there is a lot of interchangeability. The next least reusable component is the mainboard, which has a chipset and socket for a range of different CPU models, which however must be of a specified series. And then there is the CPU itself, which can only be used in a board that is specifically designed for it. It’s hard to know which of these two latter, the CPU and the mainboard, are most or least reusable, but generally a specific CPU can fit in a range of boards, and a specific board can take a range of CPUs. When it comes to the other base components of a system, the interface standards for those components change less frequently. As examples, the common SATA standard for internal disks has been around for 20 years, PCI for internal slots for 30 years, and the VGA video standard and PS/2 mouse ports for almost 35; and all of these can be found in new boards you can buy today. Analog audio is probably the oldest standard that is today almost universal in every generation of desktop PC boards ever manufactured.

A $300 system would just use a new mainboard, CPU and RAM. The last time I built such a system was around five years ago. Mainboards and CPUs are much the same price now as they were then, whilst an equivalent amount of RAM has fallen in price. Here are the base specs and current prices of a system whose components could cost under $300. All pricing is from Ascent Computers in Wellington and all includes GST.

CPU: Intel Pentium G 6400 – $104.38
This is a Pentium that falls below a Core i3 but above a Celeron. I’ve chosen Pentium G models and installed them in all new systems at home for the past six years and have been pleased with its performance/price ratio. They are dual core and until recently, before the Core i3 stepped up to four cores, there was not as much performance wise between these two models. It is definitely worth the small price increase over a Celeron, but relatively few people will see meaningful benefit from the steep price increase to the Core models.
Mainboard: Asus Prime H510M-E – $132.10
When it comes to cheaper mainboards generally they only have two memory slots which limit the amount of RAM they can have added and they may have fewer of other connectors as well. This Asus board is microATX and does only have two DIMM slots but manages to have a M.2 slot so it does come up slightly in my estimation. There are VGA, HDMI and DP video interfaces (but not DVI) and four USB ports on the rear (plus basic 3 audio). Internally there are four SATA ports, and it even manages to have one PCIe x16 slot (and a pair of x1). So the main limitation at this kind of price point is generally going to be how much RAM it can have added, but also if you have a lot of SATA devices you may find there are not enough ports for these either, especially as the M.2 slot shares resources with one of the SATA ports meaning only one can be used at a time.
RAM – around $60 for 8 GB. This is a substantial amount for an entry level system these days, but it pays to put in a good amount as there is only a small additional cost compared to 4 GB, which is pretty much the smallest that you can buy. If your mainboard supports dual memory channels you may want to consider a pair of DIMMs instead of a single one, for better performance. Beware though if your system has only 2 memory slots and you are thinking of adding more RAM later – as you may end up with having to replace the old DIMMs with bigger ones and not being able to reuse them. This is the primary reason why I prefer boards with four memory slots.

So all up our entry level system using as many recycled components as possible can just come in under $300, assuming you get all the other parts free.

I have only built these types of systems a couple of times, and only because I didn’t properly check out the specs or cut corners too much on cost grounds. First time was an Intel DG41RQ mainboard with a Celeron CPU. This particular board only has a single VGA output and therefore can only drive one display. I was able to add a cheap $50 display card to it for dual screens, but the Celeron CPU imposed a noticeable performance restriction. Second time was a Gigabyte H110M-S2H mainboard with only two memory slots, limiting it in practice to only 16 GB RAM, and only four SATA ports and no M.2 slot. I still use this as a media player. I did also buy a couple of Gigabyte E350 boards, which use the low power AMD E350 embedded CPU, in the mini-ITX form factor. These computers have difficulty in playing video so have limited usefulness today. I also have an Intel NUC with a Celeron low power CPU, which struggles to play some video and as a result also has a secondary role.

However I would recommend this type of system for building a media player, whether it uses mini-ITX or microATX form factors, with the mini-ITX form more suitable in applications requiring a compact PC, but would thoroughly recommend for mini-ITX that you buy a board that will take regular CPUs and a chassis that has a reasonably powerful PSU, the Inwin Chopin series chassis being an example with its 150 watt supply. My experience with NUCs and other embedded CPU boards (both AMD and Intel) have convinced me that with an embedded CPU system there is too much risk of getting something that is just not powerful enough. As detailed in previous posts I have preferred to use a microATX low profile desktop chassis to build my current low spec media player computers.

Next time around we’ll have a look at a mid level system with nearly all new parts for about $1000.

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