|Retro-test : Voodoo 5 6000|
|By Steven M. - 23/05/2005|
V5 6000 : Board, boot and Power
Here we are with our famous Voodoo 5 6000 revision 3700A. It is equiped with 4 VSA-100 GPUs and 128MB of SDR memory (DDR was judged too expensive for such a capacity at the time). Al lthese chips are clocked at 166MHz and the card is using an AGP 2x interface. At the time nVidia was already using DDR memory since 2 generation of GeForce cards and 3dfx really should have done the same. In fact the Voodoo 5 6000 was initially planned to work with memory clocked at 183MHz which was a very high frequency for SDR memory at the time and the costs were thus high. It would have been a better idea to use "slow" DDR instead of "fast" SDR memory, the cost was probably about the same with much less availability problems. Out test card has 16 8MB memory chips (8 on each side) clocked at 6ns (166MHz) but some earlier prototypes used 5.4ns (185MHz) RAM.
Our card is a relatively advanced prototype (revision 3700A) but we can clearly see thet the power is provided through an internal molex connector instead of the planned external power supply on the final model. To power this card we have an Enermax 365W PSU capable to give 26A on the 12V line, this should be far enough. Keep in mind that this card is still a prototype and we should not wait for a perfect compatibility or stability, same for the Amigamerlin drivers which are not official. On the Voodoo 5 6000 cards there is a known bug in the PCI system connecting the different VSA-100 chips together. At high charge like in FSAA 8x mode the card can crash. There is a workaround for this called "PCI-rework" which can be found here. Our card has been modified this way and was completely stable during our tests.
As far as we know there are around 150 Voodoo 5 6000 models in the world and around 30 working ones. On the next picture we can see the unused external power connector and the HiNT bridge which is the biggest death cause for the Voodoo 5 6000 cards in the world. On some motherboards this chip can be destroyed by a short-circuit during the boot process and this kills the whole card. Let's talk about this bridge and why it's there...
If we look at the Voodoo 5 5500 (the 2 GPU model), we can see that this card doesn't use a PCI-PCI bridge for a reason that was explained during the SLI study: the master-slave configuration of the 2 VSA-100 chips which only makes the master chip visible to the AGP bus. You need to know that until the AGP 4x specification only one peripheral could be visible on the bus, this limitation was removed with the 8x specification. The problem with the Voodoo 5 6000 is that it isn't possible to connect the VSA-100 chips directly together with the dedicated communication interface, it's limited to 2 chips. The solution is to use the PCI interface of each VSA-100 chip.
So, now each VSA-100 chip is seen as an individual PCI device, the problem is that we need to route 4 PCI devices to one PCI device on the AGP bus (working in PCI66 mode). The solution is to use a PCI 4 to 1 bridge to respect the AGP specification. At the beginning an Intel chip was used to do this but it had some stability problems, the final solution was to use a HiNT HB1-SE66 PCI-PCI Bridge that can connect 4 PCI devices working at 66MHz together.
This card, like all other, is a prototype and has multiple "not for resale" stickers on it...we can also see the 3700A revision which is one of the last produced one. You can also see the very complex PCB of the card, it was probably the cause of many delays.
On the next picture you can see what the initially planned card looks like. Instead to be in line, the 4 GPUs should have been grouped by pair to waste less space. You can also see the Intel PCI-PCI bridge and the external power supply, the big Voodoo Volts.
Now it's time for a dreaded moment: the first boot with the Voodoo 5 6000! We were quite stressed because the card could be destroyed at this point and then the only solution would be to exile to Patagonia with our friends the penguins for the rest of our lifes to avoid an horrible death, slain by furious 3dfx fans. First of all let's look at our PSU, this Enermax model has served us for years now and we are very happy with it. It has all the power for a Voodoo 5 6000 on the 12V line (maximum is 12*26 = 213W max). At this point the card would probably burn ;)
Now it's time to throw the card in our computer, you can see the monster size compared to our GeForce 2 Ultra. In this configuration the Voodoo 5 6000 would probably have had problems to fit in every case or motherboard depending on their design.
A zoom on the 4 GPUs...Hey dude, it rocks ! ;)
Here we can see the PCI-PCI HiNT bridge, the BIOS and the power stage.
Now it's time for the first boot! With a finger on the HiNT bridge and the other hand ready to switch off the PSU we power the system on...victory! The card displays BIOS version 1.16 and 128MB RAM as awaited. a funny thing to notice is that this card with 4 fans makes less noise than the GeForce 2 Ultra. The HiNT bridge isn't excessively hot too, so we are reassured.
Now it's time to boot Windows XP and install the Amigamerlin 3.1 R6 drivers and the provided 3dfx tools. When this is done, we can see that the HiNT bridge and the card are correctly detected in the device manager. About the drivers it is obvious that their development ceased at the time of the repurchase of 3dfx by nVidia and no more support was brought after this date. All the new drivers come from third party people, thanks to them. We use the Amigamerlin drivers since some months without big problems, that's why we used them again on the Voodoo 5 6000. Don't forget that theVSA-100 don't support hardware T&L and thus this is done by the main CPU when necessary (and coded).
A closer look at the drivers:
Nothing very special on the first pictures. You can just see that some screenshots ave been taken with the Amigamerlin 3.1-R1 drivers that we used at the beginning. Later we switched to the R6 revision to correct a bug avoiding Quake 3 Arena to run in a 1280x1024 resolution and permitted a general performance increase of about 5-10%. This is a perfect example of how the hardware is dependant on the software.
On these two pictures you can see the 3D rendering options in Direct3D and OpenGL modes plus some other options. Here we have activated 8x FSAA.
Then we wanted to know how much power the Voodoo 5 6000 actually needs and if there was a real need for an external power supply. We measured the amperage on the 12V line on a Voodoo 5 5500 and on the 6000. It's easy to do this, you just have to put an amperemeter on the 12V molex connector of the card and that's it. We measured these results:
So the maximal power this card needs is around 50W under 3DMark 2001 SE in FSAA 8x mode. Nowadays this seems to be an acceptable value but we have to remember that in 2000 the standard PSU shipped with computer cases was something like a 200W no-name, and taking 50W off it was a lot and made 3dfx consider to ship an external PSU to guarantee that the card would work flawlessly. The VSA-100 GPUs don't get too hot despite the fact that they are made using a 0.25 micron process, in fact the HiNT and by far the power stage are the hottest points on the card under maximal load.