GeForce 4 series

The GeForce 4 series (codenames below) refers to the fourth generation of Nvidia's GeForce line of graphics processing units (GPUs). There are two different GeForce4 families, the high-performance Ti family (NV25), and the budget MX family (NV17). The MX family spawned a mostly identical GeForce4 Go (NV17M) family for the laptop market. All three families were announced in early 2002; members within each family were differentiated by core and memory clock speeds. In late 2002, there was an attempt to form a fourth family, also for the laptop market, the only member of it being the GeForce4 4200 Go (NV28M) which was derived from the Ti line.

The GeForce4 Ti (NV25) was launched in February 2002 and was a revision of the GeForce 3 (NV20). It was very similar to its predecessor; the main differences were higher core and memory clock rates, a revised memory controller (known as Lightspeed Memory Architecture II/LMA II), Direct3D 8.1 support with up to Pixel Shader 1.3, an additional vertex shader (the vertex and pixel shaders were now known as nFinite FX Engine II), hardware anti-aliasing (Accuview AA), and DVD playback. Legacy Direct3D 7-class fixed-function T&L was now implemented as vertex shaders. Proper dual-monitor support (TwinView) was also brought over from the GeForce 2 MX. The GeForce 4 Ti was superior to the GeForce 4 MX in virtually every aspect save for higher production cost, although the MX had the Nvidia VPE (video processing engine) which the Ti lacked.

The initial two models were the Ti4400 (US$299) and the top-of-the-range Ti4600 (US$399). At the time of their introduction, Nvidia's main products were the entry-level GeForce 2 MX, the midrange GeForce4 MX models (released the same time as the Ti4400 and Ti4600), and the older but still high-performance GeForce 3 (demoted to the upper mid-range or performance niche). However, ATI's Radeon 8500LE (9100) (a slower-clocked version of the flagship Radeon 8500) was somewhat cheaper than the Ti4400, and outperformed its price competitors, the GeForce 3 Ti200 and GeForce4 MX 460. The GeForce 3 Ti500 (US$299 prior to the GeForce4 release) was rendered obsolete quickly as it could not be produced cheap enough to justify a further price drop, though it filled the performance gap between the GeForce 3 Ti200 and the GeForce4 Ti4400.

In consequence, Nvidia rolled out a slightly cheaper model: the Ti4200. Although the 4200 was initially supposed to be part of the launch of the GeForce4 line, Nvidia had delayed its release to sell off the soon-to-be discontinued GeForce 3 Ti500 chips. In an attempt to prevent the Ti4200 damaging the Ti4400's sales, Nvidia set the Ti4200's memory speed at 222 MHz on the models with a 128 MiB frame buffer—a full 53 MHz slower than the Ti4400 (all of which had 128 MiB frame buffers). Models with a 64 MiB frame buffer were set to 250 MHz memory speed. This tactic didn't work however, for two reasons. Firstly, the Ti4400 was perceived as being not good enough for those who wanted top performance (who preferred the Ti4600), nor those who wanted good value for money (who typically chose the Ti4200), causing the Ti4400 to fade into obscurity. Furthermore, some graphics card makers simply ignored Nvidia's guidelines for the Ti4200, and set the memory speed at 250 MHz on the 128 MiB models anyway.

Then in late 2002, the NV25 core was replaced by the NV28 core, which differed only by addition of AGP-8X support. The Ti4200 with AGP-8X support was based on this chip, and sold as the Ti4200-8X. A Ti4800SE replaced the Ti4400 and a Ti4800 replaced the Ti4600 respectively when the 8X AGP NV28 core was introduced on these.

The only mobile derivative of the Ti series was the GeForce4 4200 Go (NV28M), launched in late 2002. The solution featured the same feature-set and similar performance compared to the NV28-based Ti4200, although the mobile variant was clocked lower. It outperformed the Mobility Radeon 9000 by a large margin, as well as being Nvidia's first DirectX 8 laptop graphics solution. However, because the GPU was not designed for the mobile space, it had thermal output similar to the desktop part. The 4200 Go also lacked power-saving circuitry like the MX-based GeForce4 4x0 Go series or the RV250-based Mobility Radeon 9000. This caused problems for notebook manufacturers, especially with regards to battery life.

The GeForce4 Ti outperformed the older GeForce 3 by a significant margin. The competing ATI Radeon 8500 was generally faster than the GeForce 3 line, but was overshadowed by the GeForce 4 Ti in every area other than price and more advanced pixel shader (1.4) support. Nvidia, however, missed a chance to dominate the upper-range/performance segment by delaying the release of the Ti4200 and by not rolling out 128 MiB models quickly enough; otherwise the Ti4200 was cheaper and faster than the previous top-line GeForce 3 Ti500 and Radeon 8500. Besides the late introduction of the Ti4200, the limited release 128 MiB models of the GeForce 3 Ti200 proved unimpressive, letting the Radeon 8500LE and even the full 8500 dominated the upper-range performance for a while. The Matrox Parhelia, despite having several DirectX 9.0 capabilities and other innovative features, was at most competitive with the GeForce 3 and GeForce 4 Ti 4200, but it was priced the same as the Ti 4600 at US$399.

The GeForce 4 Ti4200 enjoyed considerable longevity compared to its higher-clocked peers. Debuting at half the cost of the 4600 (US$199 versus US$399), the 4200 remained the best balance between price and performance until the launch of the short-lived DirectX 9 ATI Radeon 9500 Pro at the end of 2002. The Ti4200 still managed to hold its own against several next generation DirectX 9 compliant GPUs released in late 2003, outperforming the GeForce FX 5200 and the midrange FX 5600, and performing similarly to the mid-range Radeon 9600 Pro (ATI's permanent successor to the Radeon 9500 Pro) in some situations.