Quote:In some other thread I was asking for the same thing more or less but Komponent said vddq for agp are also signaling rails. So this dude didn't cut the traces and run a VI/O to VDDQ directly. Personally I wouldn't feel comfortable having 3.3v running through my nforce2 agp bridge. What I didn't get is the possibility to run it without the vI/O to vddq but the only Italian I understand (very few) are due to French.
Quote:In the pictures this dude sews off the agp plastic restricts so that the card can fit the slot and then shoots 3.3v from the back of the board to the proper agp pin also in the back. The most interesting thing is in the beginning where he seams to manage to make the v5 post with 1.65vagp. But is it stable or its just a simple post proving a no-burn state and then to manage to get stability (as it concerns the voodoo....I have some doubts about the sodomization of the nforce) he gets the vi/o on the vddq....strange and unfortunately systran doesn't translate much of the page
Hope Komponent kicks in to the rescue
Hi, dudes,
Not that any "rescue" could came from myself over this subject, but if being asked anyway I can share my oppinion as long as it is understood that I am no owner of the absolute knoledge and that what I say is only based on my personal experience and should ever be regarded with caution. But first, sorry dudes, you could have allready noticed that I no longer visit the 3DFX Community's forums as often as I used to; but that is because of my dayly job; I am at work from morning to evening, 6 days of 7 every week, so I do not have free time to continue the work on 3DFX projects anymore, at least for this period, but I am still very happy to browse every evening here at Falconfly's Forums to see the news.
Sorry for the off-topic and back on the subject: The VDDQ lines are not signaling lines, but they supply power to the I/O lines, that are ofcourse bi-directional. A 1.5V-only AGP motherboard signals through 1.5V powered lines to the video card and a 3.3V-only video card signals through 3.3V powered lines to the mainboard. It is simple enough for everyone to understand, realy: the main problem is not the VDDQ, but the bi-directional I/O. The 2 devices must "talk" the same language or problems will arrive, sooner or later...
I see a bigger problem with this mod, though: The dude applies external 3.3V power to the AGP VDDQ pin under the MB's PCB, directly to the slot. But the electrons do not have a mind of their own, so the power applied to the pin will flow through the whole circuit: from the pin to the video card through the AGP slot, but from the pin to the MB's chipset too, through the PCB's trace, so now there is an external 3.3V power applied to it. I am sorry, but I cannot agree with that... Add that to the overvolting caused by the 3.3V VIO to a 1.5V rated item and now you have the complete picture. What I see is a torture to the setup and I do not think that it could support it for ever, but ofcourse I could be dead wrong so do not take my words for granted.
But... there could be a safe way to do a simmilar mod. As you all know, the VSA100 GPU is natively 1.5V signaling compatible along 3.3V too, but the only video card that uses this feature is the Voodoo4 AGP. A safe way to modify a Voodoo5 to work with 1.5V signaling would be to do the modding the Voodoo4 style. I will post bellow a picture with informations on how the standard selection is made for the VSA100 on a Voodoo4 AGP PCB. Ofcourse, I got the info after un-soldering the GPU out of the video card and after research and study and as always you should treat the subject with caution...
I simply had no spare time anymore to continue the project with a Voodoo5, sorry... so for now, the italian dude that did the present mod got closer than anyone to the final destination and I wish him alot of good luck to continue his work.
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