Don't know all the exact models but basicly it is like this:

Socket A Via chipset boards up to kt266a should run fine with 3,3v agp cards (like the voodoo's). Most kt333 boards should also be fine but it depends on the revision (google?), i don't know the exact numbers. Kt400, kt600, kt880 and Nforce(2) based boards are NOT supporting 3,3v agp. I have an Asus A7V333 that works fine.

No Intel chipset on p4 s478 boards support 3,3v agp, none. Only SiS based s478 boards can be compatible, don't know the exact types.

http://www.playtool.com/pages/agpcompat/agp.html

This website lists most relevant information about AGP and has a list of chipsets and GPUs that have universal AGP support.

HOWEVER. A lesson I learned with a dead motherboard to show for it, just because a chipset can support 3.3V Universal AGP it does NOT mean the individual motherboard using that chipset does. ALWAYS read the manual carefully so that you don't miss a hidden paragraph somewhere that says the board is incompatible with 3.3V cards. Seriously, AGP universal and the, lets say, "questionable" adherence of motherboard and video card manufacturers to the standards can be a royal pain in the ass.

Edit: wrong link.

Thank you all for the info,i will try to find socket A boards with the kt266, or try any luck with kt333.

Note that KT266/KT333 are still within the era of VIA not having solid AGP compliance. Radeon 8500 comes to mind since it likes to lock up or do other strange things like cause pauses or extreme slowdowns.

Sometimes you have to experiment with various drivers. The GF4 Ti 4600 that I have for example was blue screening me sometimes on 28.32 but seems ok with 43.45.

Running Windows XP instead of 98SE might help too. It's just more stable in general.

Koltoroc wrote:

, just because a chipset can support 3.3V Universal AGP it does NOT mean the individual motherboard using that chipset does.

It's more than that unfortunately. Just because a mobo has a universal AGP slot does not mean it provides 3.3v or have protection circuitry. Be careful and always use a burner card to test.

An Abit KT7A or KT7A RAID board would be a good choice. "Only" has the KT133A chipset, but with a socket wire mod and a modded BIOS, you can run Barton CPUs in it.. the motherboard maxes out at about 2.4Ghz CPU speed.

Be prepared to replace the caps on pretty much any old Socket-A board you get though. When I got my NIB KT7A, the first time I powered it up 3 or 4 of the capacitors exploded.

squiggly wrote:

It's more than that unfortunately. Just because a mobo has a universal AGP slot does not mean it provides 3.3v or have protection circuitry. Be careful and always use a burner card to test.

I know. I have a motherboard with "universal" AGP that was killed by a 3.3v card.

Basically, running a 3.3V card in a 1.5V board kills the board, running a 1.5V card in a 3.3V only board kills the card. Both have the risk of killing both, but whatever has the lower rated voltage WILL die.

swaaye wrote:

Note that KT266/KT333 are still within the era of VIA not having solid AGP compliance. Radeon 8500 comes to mind since it likes to lock up or do other strange things like cause pauses or extreme slowdowns.

Sometimes you have to experiment with various drivers. The GF4 Ti 4600 that I have for example was blue screening me sometimes on 28.32 but seems ok with 43.45.

Running Windows XP instead of 98SE might help too. It's just more stable in general.

I dont think that the voodoo 3 will have problems since it don't use any agp extensions.

When considering socket 478, the safe bet is SiS 645. Of course it is possible some 645 boards are not 3.3V compatible. But from my personal experience I can confirm at least these two are:

MSI 645 Ultra http://hw-museum.cz/mb/32/msi-645-ultra
I was using this one for quite some time in my Voodoo5 PC - it is perfectly compatible with 3.3V AGP cards, including V5 5500 AGP. The fastest supported CPU is P4 Northwood 2.8/533. Or possibly one of the "unicorn" P4 3.0/400. Beware that Northwood 3.06/533 doesn't work properly on this MB.

Asus P4S333 http://hw-museum.cz/mb/65/asus-p4s333
Similar to the MSI board, this one even works with P4 3.06 HT. I really don't remember whether HT is active or not (probably not)... but this doesn't really matter for retro gaming PC. I've tested many old videocards on this MB - starting with Rage Pro, Riva TNT and up to Voodoo3 AGP. http://hwbot.org/submission/2348413_havli_3dm … _agp_8752_marks All working well.

Other than SiS 645, also 651 might be 3.3V AGP compatible on some boards. And I believe some 3.3V AGP VIA P4 chipsets also exists, but no personal experience with them.

One more entry I'll add to havli's list:
ECS P4S5A (SiS 645)
it was tested here:
Universal AGP slot of ECS P4S5A motherboard?

some late KT333 boards are really the KT400 chipset, with AGP 8X disabled, so be careful with that.

There's a thread on the fastest motherboards that accept Voodoo cards here - Fastest motherboard that accepts a Voodoo 5500?

candle_86 wrote:

some late KT333 boards are really the KT400 chipset, with AGP 8X disabled, so be careful with that.

i found an asus a7v266-mx(KT266, seems to be compatible with my voodoo 3) with cpu and ram for about the price of a chinese food delivery, i will give it a try.

meljor wrote:

Don't know all the exact models but basicly it is like this:

Socket A Via chipset boards up to kt266a should run fine with 3,3v agp cards (like the voodoo's). Most kt333 boards should also be fine but it depends on the revision (google?), i don't know the exact numbers. Kt400, kt600, kt880 and Nforce(2) based boards are NOT supporting 3,3v agp. I have an Asus A7V333 that works fine.

No Intel chipset on p4 s478 boards support 3,3v agp, none. Only SiS based s478 boards can be compatible, don't know the exact types.

https://imgur.com/gallery/rjm40
On the a7v266-mx it mentions that it only accept 1.5v cards.

Although it doesn't guarantee functional compatibility, the notches on the AGP slot are at least supposed to prevent any electrical disasters from happening. It might be useful to keep a list of motherboards that are known to have incorrect keying on that slot, resulting in the potential for damage.
I imagine the number of badly keyed boards would be pretty small, but I know they're a worrisome minefield for people trying to use older cards on newer boards.

shamino wrote:

Although it doesn't guarantee functional compatibility, the notches on the AGP slot are at least supposed to prevent any electrical disasters from happening. It might be useful to keep a list of motherboards that are known to have incorrect keying on that slot, resulting in the potential for damage.
I imagine the number of badly keyed boards would be pretty small, but I know they're a worrisome minefield for people trying to use older cards on newer boards.

Yeah i noticed that, the board also don't fit, which is weird because on http://www.playtool.com/pages/agpcompat/agp.h … lagpmotherboard it mentions the VIA KM-266 as a universal agp capable.