Computer Speed: Part II (Platforms)
In the last article we discussed the importance of the hard disk drive. Now that you have narrowed your computer selection to those systems that include U320 SCSI hard drives with access times of less than, or equal to, 3.5ms, we move on to platform. Workstations and PCs are the two primary platforms and there is substantial architectural difference between them.
PCs, offered by companies such as Acer, Apple, Dell, E-machines, Gateway, and others, include components that are all connected to a central chipset and controlled by software on the computer. These components include the network controller (for communication with other computers such as connecting to the Internet), the video controller (for displaying images on the monitors), and other components. In addition to the components utilizing a single chipset, the connection with any single component (referred to as a "bus") is shared with other components. This means that, with a PC, when a task is being performed using one of the computer's components, the performance of other unrelated tasks can be degraded. The PC components are mostly incapable of performing their own processing, which means that software on the computer must run in the background to control these components. This leads to additional performance degradation.
Workstations, on the other hand, are designed to maximize performance. There is no single central chipset. Instead, there are multiple chipsets to which components are connected via dedicate pathways that are unaffected by the traffic of other pathways connecting other components. These various chipsets then connect directly to various processors (CPUs). In multiple CPU configurations, various CPUs can discretely control different components, allowing for all components to be used at maximum potential without degrading performance of any other component. In addition, the components that make up workstations each have their own memory and processor which means they do not need to be controlled by software, use system memory, or CPU power. This is highly significant. As an example: if you use Photoshop to open a multi-gigabyte file on a PC while you are using the same computer to apply a filter to another image, the filtering will slow down while the file is opening because the filtering is using the same components that are being used to open the file. Doing the same task on a workstation, however, would provide no performance degradation to either task because each of these tasks would use different components that are unrelated and thus allow you to do both at maximum speed.
Some companies use "Workstation" as part of a model name to imply a PC is a workstation. To determine if a computer is a good workstation, ask the provider for a "block diagram" of the system (a technical diagram showing how the components are connected) and then have someone knowledgeable with workstations interpret it for you.
The next and final step to finding a fast computer is choosing a computer with efficient controllers. This will be discussed in the next article.