Speaking of Cyrix appreciation - I bought this today. It is [almost] a Cyrix Media GXm CPU, aka Geode from National Semiconductor. According to Wiki, it is nearly identical to the original Cyrix Media GXm CPUs, but with a die shrink, that is, .18 um instead of .35 um. I have the 266 MHz Media GXm CPU in a system now, but would like to maximise the speed to 300 MHz. I am hoping that this GX1 will work in the GXm motherboard. Wiki mentions that the GX1 uses the CS5530A companion chipset, while the GXm uses the CS5530 chipset. I am hoping that the "A" suffix is only related to which onboard graphics and sound is used on the CPU. On my system I have the integrated sound and graphics disabled, so hopefully this 300 MHz GX1 chip will work.

The Geode 300/333 MHz GX1 CPU is not easily found in the PGA form factor, so I feel lucky to have got this little gem for $20 shipped. Luckily, my motherboard also supports these lower voltages.

The purple lettering is also pretty unique.

You're right; I was confused with the 6x86MX part, the 6x86MX PR200 comes in two variants, a 2.5x66MHz and a 2x75MHz. http://www.cpu-collection.de/?tn=0&l0=co&l1=C … -PR200,66MHzBus

PhilsComputerLab wrote:

66 x 2.5 is 165, so yea, the 60 x 2.5 gives you the 150 MHz.

Hey guys, so here's a question for you. Say its about 1996 or 7ish. You have a Cyrix 5x86 100Mhz (embedded to the board so you can't replace it). You want to give it a slight upgrade to handle that hot new operating system (Windows 95) but, unfortunately you're on a budget.

My guess is another 16MB of RAM (On top of the 8MB original). And obviously a CD-ROM drive of some sort.

What about video and sound? Keep in mind.. my theoretical situation is "budget". Unfortunately I'm not to familiar with this era.

Private_Ops wrote:

Hey guys, so here's a question for you. Say its about 1996 or 7ish. You have a Cyrix 5x86 100Mhz (embedded to the board so you can't replace it). You want to give it a slight upgrade to handle that hot new operating system (Windows 95) but, unfortunately you're on a budget.

My guess is another 16MB of RAM (On top of the 8MB original). And obviously a CD-ROM drive of some sort.

What about video and sound? Keep in mind.. my theoretical situation is "budget". Unfortunately I'm not to familiar with this era.

Yes, more memory will definitely improve performance.

The video card is dependent on what your motherboard supports - does it have VESA Local Bus or PCI slots?
If not, then you will have to go with a 16-bit ISA card (ISA versions of the Tseng Labs ET4000 derivative or Cirrus Logic CL-GD5426/CL-GD5428 should do nicely).
With VESA Local Bus you can look at VESA Local Bus versions of the above chipsets and also S3 chipsets.
With PCI there are many more options (there are threads on Vogons where this has already been discussed).

Sound card will most likely be an AWE32 or AWE64 (the latter was released in November 1996).

However, you can only improve your overall performance up to point, since you are still limited by your CPU's performance (it's equivalent to roughly that of a Pentium 75 MHz).
PS: You can improve the Cyrix CPU's performance a bit by the register enhancements - refer The Ultimate 486 Benchmark Comparison.

On a budget in early 1997 - simply increase the FSB from 33 Mhz to 40 MHz. Cost: free. Also, enable some of the Cyrix 5x86's special features. Cost: free.

i would think on such a low specced machine some simple scsi adapter might do, these are very cheap nowadays

jesolo wrote:

Yes, more memory will definitely improve performance. […]
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Private_Ops wrote:

Hey guys, so here's a question for you. Say its about 1996 or 7ish. You have a Cyrix 5x86 100Mhz (embedded to the board so you can't replace it). You want to give it a slight upgrade to handle that hot new operating system (Windows 95) but, unfortunately you're on a budget.

My guess is another 16MB of RAM (On top of the 8MB original). And obviously a CD-ROM drive of some sort.

What about video and sound? Keep in mind.. my theoretical situation is "budget". Unfortunately I'm not to familiar with this era.

Yes, more memory will definitely improve performance.

The video card is dependent on what your motherboard supports - does it have VESA Local Bus or PCI slots?
If not, then you will have to go with a 16-bit ISA card (ISA versions of the Tseng Labs ET4000 derivative or Cirrus Logic CL-GD5426/CL-GD5428 should do nicely).
With VESA Local Bus you can look at VESA Local Bus versions of the above chipsets and also S3 chipsets.
With PCI there are many more options (there are threads on Vogons where this has already been discussed).

Sound card will most likely be an AWE32 or AWE64 (the latter was released in November 1996).

However, you can only improve your overall performance up to point, since you are still limited by your CPU's performance (it's equivalent to roughly that of a Pentium 75 MHz).
PS: You can improve the Cyrix CPU's performance a bit by the register enhancements - refer The Ultimate 486 Benchmark Comparison.

PCI and ISA.

Most threads I found about 486 era stuff was for the high end. I'm figurin a Cirrus Logic (PCI) video card but, I'm not sure what model specifically.

Far as sound card.. would something with an ESS or Yamaha chipset fit in? I'm not sure of where these fell at in price during that era.

Private_Ops wrote:

PCI and ISA.

Most threads I found about 486 era stuff was for the high end. I'm figurin a Cirrus Logic (PCI) video card but, I'm not sure what model specifically.

Far as sound card.. would something with an ESS or Yamaha chipset fit in? I'm not sure of where these fell at in price during that era.

If you want to stay "period correct", and you're looking at (mostly) 2D PCI graphics cards, then you can look at ATI 3D RAGE II (II+,II+DVD, IIc), Alliance ProMotion AT3D, Cirrus Logic CL-GD5436, CL-GD5446 or CL-GD546x, Tseng Labs ET6000 & the S3 Virge range of graphics cards.
You can, of course, go all out and plug in a 3dfx Voodoo Banshee PCI card (or even a Voodoo Rush, if you can find one) which gives you very good 2D performance and is also a 3D graphics card. Although, you won't find many 3D games that will play satisfactory on the hardware you have.

By 1996/1997 there were many sound card players in the market and by 2000 many dropped out of the market again.
It was also around this time that many started to transition to the PCI bus for sound cards. You can either choose to go with an ISA based card (which provides better DOS support) or a PCI based card, depending on what you want to use the PC for.
Both ESS Audiodrive & Yamaha cards were quite common by that time, but I cannot recall which chipsets were on the market. As for ESS, there were the ES1688, ES1868 & ES1869 chipsets.

What feipoa stated earlier is also true, but these days I tend to be careful to overclock my old CPU's. If you want a faster system, then rather build up a Pentium 1 based system, as opposed to trying to overclock your 486 based PC.
If you do decide to increase the FSB of the motherboard, check whether your BIOS has a PCI divider. Otherwise, you will be overclocking your PCI bus as well, which means that your graphics card will also be overclocked.

Most (almost all?) Cyrix 5x86-100 CPUs will run at 120 MHz. A PCI bus at 40 MHz also provides a nice boost to your graphics. Most PCI cards will run fine at 40 MHz. The most common issues at 40 MHz are with network interface cards. If you keep your cache at 256K or less, you should be able to get away with fast cache and RAM timings still.

This is my modest Cyrix (and family) collection:

The MII is 'dead', as in when POSTing, it gets weird and skips the POST screen and tries to boot from FDD (and then crashes). Too bad, but does anybody maybe recognise this behaviour? I have tested in multiple boards (Asus TX based, Asus SP97-V (SiS chipset), AOpen AX59Pro SS7). In some boards there is no POST at all.

I have another MII in the mail (a PR333).

My 'dream' Cyrix would be the first CPU I bought with my own money, a Cyrix 6x86L-P200+GP (http://www.cpu-world.com/CPUs/6x86/Cyrix-6x86 … L-PR200+GP.html).

You guys might enjoy this one:

Building a Cyrix 6x86 DOS Retro Gaming PC

I use a 6x86L PR200+

Yes, I've seen that one 😀 THat CPU is almost perfect (my original one had Cyrix branding instead of IBM 😉)

PhilsComputerLab wrote:

You guys might enjoy this one:

Building a Cyrix 6x86 DOS Retro Gaming PC

I use a 6x86L PR200+

Nice to see a Cyrix 6x86L make it to a retro gaming build. Few people build a system around Cyrix these days. It would be really novel to see a Cyrix MediaGX gaming build for early Windows 3D and DOS 3D games.

feipoa wrote:

Nice to see a Cyrix 6x86L make it to a retro gaming build. Few people build a system around Cyrix these days. It would be really novel to see a Cyrix MediaGX gaming build for early Windows 3D and DOS 3D games.

Unfortunately I could never get my MediaGX board to post and after a bit I decided to put it back into its box and start with other projects

You need an ECS P5GX-M. These are the Rolls Royce of MediaGX boards, with 5-10x multipliers with integer increments, 2.1 - 3.5 V with 0.1 V incriments, 2xPCI, 2xISA, 2xSDRAM slots, ZIF, PS/2 mouse port, 2xUSB, 2xserial, LPT, Game/mide, and of course crummy integrated sound and VGA. It has an AWARD BIOS, which is nice, because we can hack it easily with Modbin. I am really looking forward to trying out that Geode GX1 chip in it at 300 MHz, but am engulfed in a 386 project at the moment.

feipoa wrote:

Nice to see a Cyrix 6x86L make it to a retro gaming build. Few people build a system around Cyrix these days. It would be really novel to see a Cyrix MediaGX gaming build for early Windows 3D and DOS 3D games.

MediaGX? That rings some bells. Cyrix / Geode GXM-200?

DOS Gaming PC with the Geode GXm processor

Interesting that you were unable to get 256 MB RAM going. I had no problem with 256 MB, however you must set the CAS Latency to 3T instead of 2T. Not wanting to reduce the performance any more than necessary, I dropped the RAM down to 192 MB and was able to leave the CAS Latency at 2T.

Also, there are some CPU enhancements which you can enable that Cyrix/National left disabled to broaden their system compatibility matrix. As with the Cyrix 5x86, branch prediction, Fast FPU, etc. are disabled. Unfortunately, branch prediction is also not stable on these chips, however FP_FAST is stable and is the most important item to enable. I also enable the RSTK_EN and LOOP_EN performance enhancements, although they offer little to no benefit. As with the Cyrix 5x86, the MediaGX sees an average of 18% increase in FPU performance when enabling FP_FAST. If interested, I detail how to get these registers enabled on the MediaGX here, Register settings for various CPUs . It is a convoluted process, but it seems to work. There may be some features which you can disable to get down to the 386 level.

I am not surprised you had issues with DMA on the integrated IDE port. It was a pain in the butt, but I was able to get it working. I don't remember how I did it anymore, but it is possible! I am currently using a PCI Promise ATA card though because I want to test out the Geode GX1, which uses the CS5530A chipset instead of the CS5530. I want to use as little of the integrated hardware as possible. I do remember, though, that I had to install the DMA drivers right at or just after Win98 installation. I could not get them installed later on for some reason.

Yea I'm usually pressed for time with these videos, so if I can't figure something out within a reasonable time-frame I have to move on. Good to know that there are some tweaks to be had, makes these processors a little bit more special.

One of the highlights for me is that this board is uATX, an excellent board for building something compact.

feipoa wrote:

Speaking of Cyrix appreciation - I bought this today. It is [almost] a Cyrix Media GXm CPU, aka Geode from National Semiconduct […]
Show full quote

Speaking of Cyrix appreciation - I bought this today. It is [almost] a Cyrix Media GXm CPU, aka Geode from National Semiconductor. According to Wiki, it is nearly identical to the original Cyrix Media GXm CPUs, but with a die shrink, that is, .18 um instead of .35 um. I have the 266 MHz Media GXm CPU in a system now, but would like to maximise the speed to 300 MHz. I am hoping that this GX1 will work in the GXm motherboard. Wiki mentions that the GX1 uses the CS5530A companion chipset, while the GXm uses the CS5530 chipset. I am hoping that the "A" suffix is only related to which onboard graphics and sound is used on the CPU. On my system I have the integrated sound and graphics disabled, so hopefully this 300 MHz GX1 chip will work.

The Geode 300/333 MHz GX1 CPU is not easily found in the PGA form factor, so I feel lucky to have got this little gem for $20 shipped. Luckily, my motherboard also supports these lower voltages.

The purple lettering is also pretty unique.

Cyrix_Media_GX1_front.jpg

Cyrix_Media_GX1_back.jpg

I got around to testing the GX1 300 MHz CPU today. I left the multiplier set for 266 MHz and set the voltage to 2.1 V. The system POSTed and began to boot, but, both, Win9x and NT4 would not boot properly. NT4 actually rebooted on its own without signaling an error, not even a BSOD, while Win98SE spat out some error and stopped at the DOS prompt. Unfortunately, it seems like the NS5330A chipset required by the GX1 is different enough from the NS5330 that the GX1 chip will not work on this motherboard. For completeness, I also set the jumpers up for 300 and 333 MHz, but the screen stayed all black after power-up.

Welp i finished fixing bent pins on 300GP one,seems it's time to join,here is what i have so far:

Still in slooooowest possible process of building Cyrix rig