The Intel 845 Chipset Family

All of these chipsets have the following features in common:

Beyond these similarities, however, the seven different members of the 845 are quite different. Well start with an analysis of the Intel 845 chipset, followed by comparisons with other members of the family.

The Founding Father the Intel 845

The current version of the Intel 845 (sometimes referred to as the 845D) differs from the original version by offering support for both 200 and 266MHz DDR SDRAM as well as PC-133 SDRAM (the original version was developed for use with PC-133 SDRAM only). The Intel 845s 82845 MCH supports Socket 478-based Celeron or Pentium 4 processors, and can support up to two DDR SDRAM modules or three standard SDRAM modules (depending upon the motherboard). When DDR SDRAM is used, the 845 supports either 200MHz (PC1600) or 266MHz (PC2100) memory speeds, with a front-side bus (FSB) speed of 400MHz. The 845 supports ECC error correction when parity-checked memory modules are used. It offers an AGP 4x video slot, but has no onboard video.

The 845 uses the same ICH2 I/O controller hub chip (82801-BA) used in the Intel 850 and 850E chipsets, which are Rambus-based systems, and also appeared in the 815EP, which is for a low-cost SDRAM-based system. The ICH2 supports ATA/100 hard disk interfacing, basic AC97 sound, and four USB 1.1 ports (you can learn more about the ICH2 in Chapter 4 of my book Upgrading and Repairing PCs, 14^th Edition). The features of the 845 make for a solid system, but also indicate that the 845 is a bit behind the cool technology curve. If you need USB 2.0 support, enhanced audio, or on-board video, you need to consider other members of the 845 family.

Integrated Video Versions Intel 845GL and 845GV

Low-cost chipsets with integrated video are nothing new: the Intel 810 was one of the first to popularize this trend. However, the Intel 810 and 815 series werent designed to work with the Pentium 4 or Celeron 4 processors and didnt offer advanced 3D graphics. To provide low-cost 3D integrated video for Pentium 4 and Celeron-based systems, Intel created two low-cost versions of the 845, the 845GL and 845GV.

The 845GL supports the same types of memory and FSB speed as the original 845, while the 845GV supports SDRAM and DDR memory, but with FSB speeds up to 533MHz. Neither the GL nor the GV versions support ECC error correction, and both replace the ICH2 with the newer ICH4 I/O controller hub. The major improvement in the ICH4 over the ICH2 is the ICH4s support for six USB 2.0 ports. Thus, chipsets which use ICH4 are better platforms for users with a lot of USB 1.1 devices (USB 2.0 supports multiple USB devices better than USB 1.1 does) or who have HiSpeed USB (USB 2.0) devices such as external CD burners or hard drives. Although both the GL and GV chipsets use ICH4, the GV version offers enhanced 20-bit audio (providing true surround sound output) for better sound quality.

Both the GL and GV models use 32MB of system RAM for video on systems with 128MB up to 255MB of system RAM, and 64MB on systems with 256MB or more system RAM. Both chipsets support interfacing to flat-panel LCDs and TVs as well as conventional CRT monitors. These chipsets support Intels Extreme Graphics Architecture for improved 3D performance. The technologies built into this architecture are discussed later in this article.

Integrated Now, AGP Later with the Intel 845G and 845GE Chipsets

While integrated video reduces system costs up-front, most integrated chipsets leave users dangling when its time to improve performance because they dont offer an AGP 4x slot. The Intel 845G and 845GE chipsets offer the best of both worlds because they offer integrated video for initial use plus an AGP 4x slot for future high-performance video upgrades.

Both the G and GE chipsets support 533MHz FSB, but they differ in the types of memory they support. The G model supports both standard and DDR SDRAM, while the GE model supports only DDR SDRAM. Neither support ECC error correction, while both use the ICH4 I/O controller hub. In keeping with its support for fast memory, the GE models integrated graphics runs at a core speed of 266MHz, while the G models integrated graphics run at only 200MHz. Both use the same video memory sizing rules as the GL and GV models do when integrated video is used. Both chipsets offer enhanced 20-bit audio and support for digital video and TV-out. These chipsets also support Intels Extreme Graphics Architecture for improved 3D performance, discussed later in this article.

The 845E and 845PE

Despite the similarity in names, these last two members of the 845 family differ from each other in some significant ways. Both chipsets support FSB speeds up to 533MHz, DDR SDRAM, and use the ICH4 I/O Controller hub with enhanced 20-bit surround audio. However, the 845E also supports ECC error correction, making this chipset an updated version of the 845. The 845PE drops support for ECC error correction and 200MHz DDR memory, but is among the first 845-series chipsets to support PC-2700 (333MHz) DDR SDRAM.

Comparing the Chipsets

With seven different models to choose from, selecting the right 845-series chipset can be tricky. Use Table 1 to provide an overview of the major differences between each of these chipsets.

Table 1 845-series Chipsets by Feature

The chipsets are listed in power from left to right, and are separated by whether they have integrated video or not. In general, the best chipset with integrated video is the 845GE, and the best chipset without integrated video is the 845PE. As Table 1 makes clear, different members of the 845 family are best suited for different tasks. To learn more, select a chipset name in Figure 1 and see the schematic diagram for that chipset.

Figure 1

845 Chipset | 845E Chipset | 845G Chipset | 845GE Chipset | 845GL Chipset | 845GV Chipset | 845PE Chipset

Intel Extreme Graphics Architecture

845-series chipsets with integrated video (845G-series models) support Intels new Extreme Graphics Architecture, which supports 3D graphics and features four technologies to improve 3D rendering speed and quality:

While Extreme Graphics Architecture improves 3D rendering compared to Intels earlier integrated video chipsets, the 810 and 815-series chipsets, which had no 3D functions at all, its performance and features still lag behind even current mid-range video chipsets from nVidia and ATI. Extreme Graphics Architecture lacks hardware Transform and Lighting (T&L) features, a feature required by some of todays most popular games, and offers frame rates which, at best, are about the level of the low-end nVidia GeForce 2 MX 200. Thus, while you can play an occasional game with the G-series systems with integrated video, if you want serious game play, youre much better off with one of the 845 models which support AGP 4x and DDR333 memory such as the 845GE or 845PE.

Hyper-Threading (HT) Technology

If youre considering moving to a 3GHz or faster Pentium 4 processor or a new motherboard or system based on an 845-series chipset, the issue of Hyper-Threading (HT) technology support is very important. What is Hyper-Threading? Simply put, its a method for turning a single physical processor into two virtual processors, with each virtual processor handling different threads (series of tasks). This is also called Thread-level parallelism, or TLP), and the new 3.06GHz and higher Pentium 4 processors support it. HT is designed to improve CPU utilization by as much as 40%, particularly when the processor threads are not trying to use the same resource. Benchmarks are showing that the normal gain in performance is about 20%, meaning that merely turning on HT technology can improve overall processor performance by that amount on average. This is like turning a 3.06 GHz processor into a 3.7 GHz processor! To be able to activate and utilize the HT Technology, you will need the following:

All 3.06 GHz and faster Pentium 4 processors support HT Technology. All 845-series chipsets with 533MHz FSB support will support HT-enabled processors, except that the 845G chipset supports HT only in the B-1 or higher steppings of the chipset. The motherboard BIOS must support HT Technology, and there is a setting which must be enabled. Finally, you will also need an operating system designed to support dual processors, currently the only operating systems that support HT Technology are Windows XP Home and Professional editions.

Intel Application Accelerator

All members of the 845 chipset family support the Intel Application Accelerator (IAA), a driver which provides faster disk I/O, quicker boot times, 48-bit LBA (over 137GB) hard disks, automatic selection of fastest DMA transfer rates for ATA devices, and other benefits. Specific versions of the Intel Application Accelerator vary according to whether you use Windows XP or other Windows versions. See the Intel Application Accelerator Web site for details and to download the latest version of the IAA for your version of Windows: http://support.intel.com/support/chipsets/iaa/index.htm

Which 845 Is the Fastest?

In a survey of recent reviews from noted hardware review sources, its clear that the 845PE and GE chipsets are the fastest members of the family, thanks in large part to support for DDR333 memory and a 533MHz FSB speed. The 845PE and GE are identical except the GE also includes integrated video, which allows a lower cost system to be constructed (no separate video card is required). The integrated video in the 845GE is not quite as fast as a separate AGP 4x card, but the integrated video can be disabled and replaced by an AGP 4x card for greater performance if desired.

Conclusion

The 845 chipset family from Intel offers a wide range of performance and features, no matter what level of system performance you want. Motherboards using various members of the 845 family are available from Intel and most other major motherboard vendors.

Intel Website Resources

Get more details about the 845 family and other Intel chipset from the Intel Chipsets page at
http://developer.intel.com/design/chipsets/

Extreme Graphics Architecture is discussed at
http://developer.intel.com/products/desk_lap/chipsets/graphics/index.htm

The Intel site for Hyper-Threading Technology is located at
http://developer.intel.com/technology/hyperthread/

Benchmark Tests of Motherboards Using 845-Family Chipsets

ExtremeTech reviews the 845PE at:
http://www.extremetech.com/article2/0,3973,590200,00.asp

Sharkey Extreme reviews the 845G at
http://www.sharkeyextreme.com/hardware/motherboards/article.php/10703_1141511__1

Anandtechs review of the 845G and 845E chipsets
http://www.anandtech.com/showdoc.html?i=1624&p=10

Toms Hardwares reviews of motherboards using the 845G include
http://www17.tomshardware.com/mainboard/02q3/020917/index.html
http://www17.tomshardware.com/mainboard/02q3/020722/index.html

Toms Hardwares reviews of the 845E:
http://www17.tomshardware.com/mainboard/02q3/020708/index.html