Cirrus Logic

Cirrus Logic was a graphics chipset manufacturer for the IBM PC and its compatibles. Founded in 1984 in Silicon Valley, their chipsets became very popular due to their low cost and high degree of compatibility. During the early 90s, when compared to other Windows graphics accelerator cards from Trident, Oak, and Paradise (Western Digital), the Cirrus Logic usually outperformed them all.

In 1991 the company acquired Crystal Semiconductor, an audio mixer/DSP chip company.

CL-GD410 / CL-GD420

Launched: 1987
Bus: 8-bit ISA

The CL-GD410 and 420 was an ISA Super VGA chipset. This chipset can be found on the Video7 VEGA VGA card.

 

 

CL-GD510 / CL-GD520

Launched: 1988
Bus: 8-bit ISA
Memory: 256 KB DRAM
Supports: Hercules, CGA, EGA, MCGA, VGA

The CL-GD510 and 520 was an ISA Super VGA chipset, called "Eagle II". This chipset was known for its 100% hardware CGA emulation. Most cards that bore this chipset came with both 9-pin and 15-pin D-SUB sockets to support pre-VGA monitors and VGA/SVGA/Multisync monitors. The core was typically clocked at 40 MHz, as was the memory.

I have one of these cards - it is an almost full-length 8-bit ISA card that runs the Eagle II VGA chipset. I dumped the VGA BIOS v2.12 here (the file is 64 KB but I believe the Eagle II is just in the first 32 KB so you will need to edit the file to make it work for re-burning).

The Ultimate Oldschool PC Font Resource has this card's incredible font in its collection:

Used on the MaxLogic MX675, VIP VGP-II, Morse KP800-16, and VG-1000.

 

 

CL-GD5320

Launched: 1990
Bus: 16-bit ISA
Memory: 256 KB DRAM
Supports: VGA

The CL-GD5320 was an ISA Super VGA chipset. These cards, since they were VGA only, came with just the 15-pin D-SUB. The core clock ran at 40 MHz.

Found on the CVGA-V3-256, VP442, VP44.

 

 

CL-GD5401

Launched: 1991
Bus: 16-bit ISA

The CL-GD5401 was an ISA Super VGA chipset, also known as Acumos VGA, or AVGA1. This was the first fully-integrated VGA chip to market. They were sold on the basis of low price rather than high performance, but despite this, both the AVGA and AVGA2 are top performers!

Found on the EIZO VA30, KT-AVGA1-V2, and Cornerstone ImageAccel PC161i cards. Some of these cards are 16-bit ISA but still work in an XT's 8-bit ISA slot in "compatibility" mode:

 

 

 

CL-GD5402

Launched: 1993.
Bus: 16-bit ISA

The CL-GD5402 was an ISA Super VGA chipset, also known as Acumos VGA, or AVGA2. Like the AVGA1, the AVGA2 was sold on the basis of low price rather than high performance, but despite this, both the AVGA and AVGA2 are top performers!

Found on RT-3201

CL-GD5410

Launched: 1991
Bus: 16-bit ISA

The CL-GD5410 was an ISA Super VGA chipset. It was installed on low-to-mid range DRAM-based cards (accelerated), and some laptops. It is known for being among the first to integrate the graphics card components into a single chip (built-in RAMDAC and clock generators).

 

 

 

CL-GD5420 / 5421


Launched: 1992.
Bus: ISA 16-bit
Memory: 512 KB or 1 MB FPM
Memory Clock: 50 MHz
Core Clock: 75 MHz

The CL-GD5420 was an ISA Super VGA chipset. Highly integrated (15-bit RAMDAC and PLL). The 5421 is a 16-bit RAMDAC. The core clock runs at 75 MHz, and memory at 50 MHz.

Found on:

  • Octek AVGA-20 (EP20069R21)
  • Ahead AVGA3B
  • FCC ID KJDKEN-CL542XVGA (see pic above with 512 KB VRAM)
  • ATI VGA

 

CL-GD5422 / 5424


Launched: 1992
Bus: ISA 16-bit (CL-GD5422) or VLB (CL-GD5424)
Memory: 512 KB or 1 MB FPM
Memory Clock: 50 MHz
Core Clock: 80 MHz

 

The CL-GD5422 was an enhanced version of the CL-GD5420, with a 32-bit memory bus and 15/16/24-bit RAMDAC, so supported True Color.

It offered 1280 x 1024 interlaced or 1024 x 768 non-interlaced maximum resolution. The CL-GD5422 supported hardware acceleration for both 8-bit and 16-bit color depths. It was one of the lowest-priced SVGA controllers to support both. The core clock runs at 80 MHz, and memory at 50 MHz.

A VESA Local Bus version of the 5422 is called the CL-GD5424.

Found on:

  • Gainward VGA-GWV27 (FCC ID: ICUVGA-GWV27) - max. resolution 1024x768
  • Ahead AVGA3-22-1M (FCC ID: 17TGD5422DM2)
  • Pine Technology PT-521/3 (FCC ID: J6QGD5422DM2)
  • RT3204
  • Unknown brand (FCC ID: GC8LA524)

The CL-GD5424 was also the integrated VGA chipset used on AST Bravo 486 computers.

Datasheet

 

CL-GD5425


Launched: 1993
Bus: ISA 16-bit or VLB
Memory: 512 KB or 1 MB FPM
Memory Clock: 60 MHz
Core Clock: 80 MHz

The CL-GD5425 was the same as the GC5424 but also got a TV out connector. This was able to scale a full VGA display (640 x 480) into a TV viewing area while maintaining a correct aspect ratio.

Datasheet

 

CL-GD5426


Launched: 1993
Bus: ISA or VLB
Memory: 1 MB or 2 MB FPM
Memory Clock: 50 MHz
Core Clock: 80 MHz
RAMDAC: 24-bit

The first Cirrus Logic chipset that got a 32-bit hardware BitBLT (bit block transfer) engine and also the first to support up to 2 MB of video memory. 15-pin D-SUB only.

Core clock runs at 80 MHz, memory at 60 MHz.
The ISA bus version could operate at up to 12.5 MHz while the VLB version ran at 50 MHz.

Found on:

Datasheet

 

CL-GD5428


Launched: 1993
Bus: ISA (16-bit) or VLB
Memory: 1 MB or 2 MB VRAM or FPM
Memory Clock: 50 MHz
Memory Sockets: Typically 20-pin DIP
Core Clock: 80 MHz
RAMDAC: 24-bit

An enhanced version of the CL-GD5426 with a faster BitBLT engine. Core clock runs at 80 MHz, memory at 50 MHz.

Found on:

  • SPEA / Video7 Vega
  • Diamond SpeedSTAR Pro VLB (FCC ID: FTUVL5426A)
  • Octek VL-VGA-28 (EP20094R11)
  • Pine PT-524/8G
  • EliteGroup / ECS VI-710/711 (FCC ID: H9NVI710)
  • VGA GUI 2100 (FCC ID JPM2100VIDE)
  • UTD-01B Cl542X VESA Local Bus
  • Palm VL-Bus (FCC ID KGBPALMVL)
  • ST242X-VL4 (FCC ID J6N4LVLDM7)
  • Gainward (FCC ID: ICU VGA-GW 143B)
  • GP-3200
  • PWA-MVA-542X (FCC ID: JCC MVGA-524X)
  • P202 (FCC ID J6N4LVLDM7)
  • DFI WG-1000VL/4
  • FCC ID KBIA3U5428
  • FCC ID: I7EAB-5426VL
  • FCC ID: J4UVGA826WVLC3
  • FCC ID: LII5428BVL
  • FCC ID: EUD 5U9 BRI461Q
  • FCC ID: KDECIRRUS5426VL

Datasheet

 

CL-GD5429 / CL-GD5430


Launched: 1994
Bus: VLB or PCI
Memory: 512 KB, 1 MB or 2 MB FPM
Memory Clock: 60 MHz
Core Clock: 86 MHz

An enhanced version of the CL-GD5428, and the first in their new "Alpine" series of chips.

What is new over prior GD-542x chipsets is the 5429/30 now supports a higher memory clock speed (32-bit memory bus) and has memory-mapped I/O.

32-bit BitBLT engine.

The CL-GD5430 is similar but has a 543X core (32-bit host interface).

Found on the following:

  • Diamond SpeedSTAR SE VLB
  • Unknown brand (FCC ID J6NGD543XPCI)
  • ProLink MVGA-AlpinePCI

Datasheet

 

CL-GD5434 / 5436


Launched: 1994.
Bus: ISA, VLB and PCI
Memory: Up to 4 MB
Memory Clock: 60 MHz (5434) or 80 MHz (5436)
Memory Sockets: Typically 40-pin SOJ
Core Clock: 135 MHz
RAMDAC: 15/16/24-bit

The Alpine family chip now with a 64-bit internal memory interface. Only supports 64-bit mode if equipped with 2 MB memory. Commonly equipped with 1 MB.

64-bit BitBLT engine.

The CL-GD5436 was simply an optimized version of the 5434, adding support for EDO DRAMs.
Only the CL-GD5434 was also available on the ISA bus.

Found on:

  • Diamond SpeedStar 64
  • Diamond SpeedStar Pro SE
  • Orchid Kelvin 64
  • MVGA Alpine PCI
  • Fastware VC922C (CL-GD5434)
  • Unknown Brand FCC ID: EJMPCICL543X
  • Unknown Brand VCC34 (FCC ID: KEGPTPCIVGA3A)
  • Unknown Brand FCC ID: IFTGD543XPCI
  • Unknown Brand FCC ID: ICUVGA-GW203
  • Unknown Brand FCC ID: J6NGD543XPCI

Datasheet

CL-GD5440


Launched: 1995
Bus: VLB or PCI
Memory: 512 KB, 1 MB or 2 MB FPM
Memory Clock: 60 MHz
Core Clock: 86 MHz
RAMDAC: 24-bit

Essentially a CL-GD5430 with an integrated CL-PX2070/'85 motion-video acceleration (CL-GD54M40 has integrated filters). The core clock runs at 86 MHz, the memory at 60 MHz.

Found on:
FCC ID: FQI54X62L

Datasheet

CL-GD5446


Launched: 1996
Bus: PCI
Memory: 1 MB or 2 MB EDO

64-bit Alpine VisualMedia accelerator. 2D-only. Adds motion-video acceleration to the CL-GD5436.

Found on:
STB Nitro 64V
FCC ID: FQI54X62L
FVGAP-CL8
SR-V641-E
Palit Microsystems Inc Daytona 64E (FCC ID: KC8GUIVGAS1)
FCC ID: KBIGD544XP

 

CL-GD546X


Launched: ?
Bus: ?
Memory: ?

The Laguna VisualMedia family of 2D, 3D, and video accelerators. the CL-GD5464 and 5465 include 3D acceleration (PCI or AGP). These chips use a single channel of RDRAM memory, providing up to 600 MB/s bandwidth. The '62 lacks 3D acceleration. All include a BitBLT engine, video windows, and 64×64 hardware cursor.

Found in MSI motherboard add-in, MS4415

CL-GD5480


Launched: ?
Bus: ?
Memory: ?

64-bit Alpine accelerator with 100 MHz SGRAM.