Installing RAM, DDR2, DDR and RDRAM
Installing Video Cards (PCI Express and AGP) and Modems
Installing Hard Drives, CD Recorders and/or DVD Recorders
My illustrated guide to replacing a motherboard. |
Full size flowchart with text: |
Choosing a motherboard is actually something of a backwards process, because the motherboard will determine which CPU and RAM you can use. In most cases, I advocate picking a CPU first and then looking at your available motherboard options. It makes sense especially at the high-end, where the CPU will be the most expensive component in your PC. The only circumstance where I would choose a motherboard before a CPU is if you have expensive legacy adapters, older PCI or even ISA adapter that you are married to for industrial use reasons, and you require a motherboard featuring the proper number of legacy slots.
The 4th edition of Build Your Own PC features three different motherboard and CPU combinations, representing the latest in mainstream PC technology. The first build is a Pentium 4 LGA (Land Grid Array), the new Intel CPU package design for Socket 775. The motherboard used was an Intel D925XCV, which Intel kindly provided with the CPU, which was pre-production at the time I did the photography for the book. I'd actually put off doing the 4th edition for almost a year while waiting for Intel and AMD to release the platforms that would have a little shelf life, and the Socket 775 design with DDR2 support should remain the desktop computer flagship for Intel for a while. The motherboard also features the new PCI Express standard for the highest speed video card support, double the throughput of AGP X8.
However, it's been AMD that's been pushing the performance barrier for desktop computers the past couple years, and we used an ASUS ABV Deluxe motherboard to support a Athlon 64 3800+ CPU. The ASUS motherboard supported 8X AGP, two banks of DDR, built in Gigabit networking, and didn't buckle under the weight of that huge chunk of copper called a heatsink:-) Both of these motherboard were standard ATX boards and could have just as easily been built in the other's corresponding case.
The Pentium 4 in Socket 478 with RAMBUS RDRAM (RIMM) was held over from the third edition, in part to illustrate the RDRAM, and in part because of the SCSI drive option. The motherboard was a D850MD, which is really a small format ATX, but was available pre-production back when I was doing the third edition. All of these motherboards featured full I/O cores with sound, I/O ports and USB, with the newer motherboards going over the top with 6.1 and 7.1 sound!
The second chapter of the book discusses choosing a motherbard and getting the most bang for your buck with components, which roughly translates into, "buy a middle of the road CPU in the latest technology (in case you need to upgrade) with a middle of the road motherboard." It's really a question of buying what you need with the option to expand, since after you build your own PC you'll be ready and willing to upgrade it when the price of the $800 CPU falls to $100.
The illustrated guide below can't be updated due to my non-compete with McGraw-Hill. Click on B/W thumbnails for fullsize color images, use "Back" button on browser to return.
| The first thing that will be apparent to the first-time Pentium II or Celeron builder is the lack of a CPU socket (note these sockets have returned again with Pentium 4's and Athlons). This Intel design utilizes a CPU slot, positioned horizontally just behind the edge mounted I/O ports. The adapter card bus slots, starting from the left, are (2) 16-bit ISA, (4) 32 bit PCI, and (1) AGP (Accelerated Graphics Port), right behind the round battery. |
Intel PD440FX Motherboard |
ATX Motherboard I/O core |
The ATX standard provides for all of the standard I/O ports to be mounted directly on the edge of the motherboard. There are five or six standard "cores" defined by Intel for arranging the port connectors. From left to right here, the stacked keyboard and mouse ports, stacked USB ports, printer and game along the top, two serial and sound along the bottom. |
| The 3 horizontal slots are for DIMMs, Dual Inline Memory Modules, that replaced the older 72pin and 20 pin SIMMs. The white latching mechanisms are automatically engaged when the DIMM is properly seated. The white 20 pin connector to the lower-right is the ATX power supply connector, the 2 horizontal black connectors to the left are the IDE ports, the floppy port is under the power connector. |
DIMM Slots and other connectors |
CPU and heatsink bracket |
The black framework rising up from the board is held in position around the CPU slot by four captured screws (it's really more visible in the color blowup). The bracket hold the P-II SEC, Single Edge Cartridge, without additonal parts, the Celeron board and heatsink require a top cover for the bracket. |
| The ATX motherboard is mounted to the pan using brass standoffs only! No more irratating plastic sliding mounts. The holes in the pan are labled for different motherboard forms, but the best approach is still to line up the holes by eye and add standoffs wherever possible. Always make sure you put in as many screws as standoffs. Otherwise, you probably misplaced a standoff which is waiting to short out your motherboard. |
Attaching motherboard to pan |
Step-by-step PC Repair Troubleshooting Techniques and Running a Computer Repair Business