Installing RAM, DDR2, DDR and RDRAM
Installing Video Cards (PCI Express and AGP) and Modems
My illustrated guide to replacing RAM |
Full size flowchart with text: |
We selected the three builds in the 4th edition of Build Your Own PC to illustrate the full range of technologies in use today, including all three of the basic RAM technologies used for main memory: DDR2, DDR and RDRAM. DDR2 is the memory of choice for the latest Socket 775 Pentium 4 systems, offering lower power consumption and lower heat dissipation than standard DDR. Motherboards only support one type of RAM (would be expensive and somewhat silly to feature two types of memory technologies on a single board), so this was one of the overriding factors in holding over the socket 478 Pentium 4 from the 3rd edition.
There's not a lot to differentiate the physical installation of DDR2 from DDR from the procedural aspect, but we present a series of step-by-step photographs for both the Pentium 560 and the Athlon 64 systems. The RDRAM used with the Pentium 4 in socket 478 is another story, as RDRAM requires the installation of continuity modules (CRIMMS) in empty banks.
Selecting RAM for your motherboard isn't a complicated matter since you're limited by the motherboard you've chosen, in terms of technology (DDR2, DDR or RDRAM), speed, and capacity. RAM is so inexpensive, at least compared to the bad old days, that I recommend in the book no less than 256MB under any circumstances, and build each of the newer systems with 1 GB. Both the RDRAM and the high speed DDR used with the Athlon 64 feature metal heat dissipating packages over the chips, while the DDR2 modules don't require any special cooling.
This illustrated guide to building a PC 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.
| We install the DIMMs with the motherboard and pan still out of the case. You can see the two alignment notches in the contact edge of the DIMM, and the two blocking keys in the socket, so the DIMM will only go in one way. The minor increase of static electricity risk working outside the case is well worth getting the DIMMs in without damaging them or the sockets. |
32 MB DIMM over socket |
Seating the second DIMM |
The new style DIMM sockets have one disadvantage vs. the older "lean in" SIMM sockets. You need to apply a good deal of force to make the DIMM engage the locking mechanism and seat properly. Definitely a two thumb job. |
| Here we see the ATX motherboard, mounted on the pan, ready for installation into the case. The CPU (a Pentium II) and heatsink havebeen installed, and the heatsink fan has been connected to the motherboard. Two SDRAM DIMMs, 32MB each, have been installed. |
ATX motherboard ready for installation |
Installing the motherboard pan |
When installing the motherboard pan (with motherboard, CPU and RAM mounted) back in the case, you want to be very sure that you don't accidentally crush any cables or onboard components when moving the pan into place. Normally, the pan hinges along one edge when aligned properly. Don't procrastinate putting the all of the screws attaching the pan to the frame back in once the pan is positioned. |
| Once the pan is installed, the motherboard is ready to be electrically connected to the case power supply and drives. You can see in the picture the extra mounting holes in the pan for motherboards of a different form factor. |
Motherboard top view in case |
Connecting the ATX power supply |
The 20 lead ATX power supply connector replaces the P8 and P9 connectors of the older AT power supplies. The connector is keyed to go on one way, and is generally as easy to install with the pan inside the case as out. |
| The ATX design usually leaves enough room to attach all of the case LEDs (lights) and switch leads with the motherboard installed. LED and switch leads are often labled, power, HDD (hard drive), keylock, right on the leads, but if not, you'll have to follow them back to the front of the case and read off the faceplate what they are. |
Case LEDs and switch leads |
I/O core from case back |
With the motherboard pan installed in the ATX case, you can now see the I/O core ports through the openings in the metal I/O shield. Most case manufacturers provide a metal bezel that fits around all of the ports, providing RF shielding and pictorial or text labels for the ports. |
Step-by-step PC Repair Troubleshooting Techniques and Running a Computer Repair Business