In a previous article, I pimped a good old Socket 7 based PC with a K6-II 400 (overclocked to 500Mhz) and a Riva 128. For sure it was running very nicely, but I found two components to make what is probably the ultimate socket 7 upgrade : a K6-III and a Voodoo 3 ! Ultimate because the K6-III is the latest et fastest socket 7 CPU and the Voodoo 3 is the best PCI card such a CPU could afford.
This is the story of my ultimate socket 7 upgrade…
K6-II VS K6-III
My K6-II is a 2.2v version which is easily overclockable to 500Mhz at 2.24v. Unfortunately, it is not the same story for the K6-III. I got a 2.4v version and at 2.5v, it does no go over 415Mhz (FSB 83Mhz and x5 multiplier). However, I managed to get it stable at 456 Mhz with 2.8v ((FSB 83Mhz and x5.5 multiplier). This CPU is just not capable of running faster.
So the question is : is a K6-III 456Mhz faster than a K6-II 500Mhz ? By changing the CPU, did I upgraded or downgraded my retro-PC ? To get a clear answer, I ran the same benchmarks as explained on my previous article. Note that i also kept the same optimizations and BIOS Tweaks.
Memory benchmark
I used Sandra 2001 V7.
| K6-II 500Mhz | K6-III 415Mhz | K6-III 456Mhz | |
|---|---|---|---|
| ALU/RAM | 117 MB/s | 123 MB/s | 124 MB/s |
| FPU/RAM | 136 MB/s | 134 MB/s | 134 MB/s |
I did also run some other benchmarks, but I did not keep track of all the values. So I can just share the K6-III 456Mhz results
3DMarks99
Games benchmarks
The results are presented as FPS. Doom and Quake are original versions with no 3D acceleration. Quake 2 is the 3DNow OpenGL optimized version. Both Quake version was running at a 640×480 resolution.
| K6-II 500Mhz | K6-III 415Mhz | K6-III 456Mhz | |
|---|---|---|---|
| Doom | 116 | 133 | 133 |
| Quake | 21.5 | 20.3 | 21.1 |
| Quake 2 | 32.7 | 36.2 | 37.8 |
And the winner is…
The K6-III at 456Mhz is the winner in terms of performances, but it is not really a KO. Overall it is only between 7 to 15% faster than the K6-II at 500Mhz on my configuration. The L2 cache of the K6-III seems to be a better bet than the additionals 50 Mhz of the K6-II.
However, keep in mind that the K6-II ran with 2.24v whereas the overclocked K6-III needs 2.8v. So in terms of efficiency, the K6-II wins.
Voodoo 3 3000 PCI : the real boost
Installing a cooling fan
The Voodoo 3 is well known for its high temperatures and the stock heatsink seems a bit light. As I wanted to try some overclocking, I skrewed a 80mm thin fan on the heatsink.
Clean replacement of the Riva 128
In order to clean up the system regarding the previous Riva 128 installation, I did the following:
- Booted in safe mode
- Launched Driver cleaner pro (1.5 build 14), clean nvidia drivers
- In System properties, display adapters, removed “Nvidia riva 128”
- Saved display settings with 640×480 16 colors, which triggered a restart
When Windows has restarted, it installed a “standard VGA card”. From here I installed the Voodoo 3 drivers from http://pa3pyx.hostronavt.ru/voodoo3.html
I also downloaded the 1.3.05 drivers from https://www.philscomputerlab.com/drivers-for-voodoo-3.html because some games (like Screamer Rally) need older glide2x.dll and glide2x.ovl
Overclocking and modded BIOS
I know that some tools exists to overclock and even make a custom BIOS. But I did not needed all that as I found someone on the web that already made a custom tweaked BIOS for the exact same card as mine : a Voodoo 3 3000 PCI with SDRam ! He also provides all the details to understand why he tuned some values : http://pa3pyx.hostronavt.ru/voodoo3.html?i=1.
So I downloaded his 21512MOD.ROM file and did I follow:
- Got the bios recover tools from 3dfxzone.it from https://www.philscomputerlab.com/drivers-for-voodoo-3.html and unarchived it
- Copied the bios file to the “recover” directory,
- Put a blank floppy disk and executed the “makedisk.com”.
This created a bootable floppy that automaticaly flash the bios when booting on it. After the BIOS upgrade, Windows reapplied the drivers and rebooted.
The modded bios set the default clock to 200 Mhz instead of 166Mhz, but I had to change the frequency to 190mhz to make it runs stable (the drivers I installed allows to change the frequency). I also changed some settings as follow.:
- Direct 3D
- Alpha blending Mode : smoother (improve the pixel fill rate)
- Hardware T&L Emulation : Enable (3DNow transform and lighting assist)
- Vertical Sync : disable
- Glide / OpenGL:
- Alpha blending Mode : smoother (improve the pixel fill rate)
- CPU Type : AMD K6-2/III (enabled 3Dow optimizations)
- Vertical Sync : disable
Benchmarks
Let’s start a base comparison with the sames games used previously. All tests have been done with the K6-III running at 456Mhz. Results are in FPS.
The benchmarks are based uppon the following commands:
- Doom: doom -timedemo demo1
- Quake: timedemo demo3
- Quake 2: timedemo 1
- Quake 3: \disconnect, then \timedemo 1 then \demo demo001
| Riva 128 | Voodoo 3 3000 stock | Voodoo 3 3000 + modded BIOS (190Mhz) | |
|---|---|---|---|
| Doom | 133 | 132 | 142.5 |
| Quake 640×480 | 21.1 | 23.8 | 25.2 |
| glQuake 1280×1024 | n/a | 55.1 | 61.4 |
| Quake 2 640×480 | 37.8 | 56.8 | 62.1 |
| Quake 2 1024×768 | n/a | 56.8 | 62.1 |
| Quake 2 1280×960 | n/a | 51.6 | 55 |
| Quake 3 1024×768 | n/a | 30.7 | 31.5 |
Finaly, a comparison of 3DMarks99 results between the old configuration (K6-II 500 + Riva 128) and the new one (K6-III 456 + Voodoo 3 3000 PCI) :
Conclusion
Let’s answering the question “is this upgrade worth it ?”: definitly yes ! If the K6-III does not boost more than 7-15% the initial performances, the Voodoo 3 has brang this PC to another dimension by literaly doubling its performances in 3D accelerated games. This PC is now able to not only run early 90′ DOS games, but also run very well lates 90′ and early 2000 games (let alone 3DFX only games). Maybe I should put my hands on a Super Socket 7 motherboard to get a 100Mhz FSB without compromising the compatibility nor the form factor.
