3.3v and 1.5v keying is built into the card. Cards with both keying support both voltages.

So if it physically fits, it's fine.

See: https://en.wikipedia.org/wiki/Accelerated_Gra … t#Compatibility

The HD3850 uses AGP 3.0. AGP should have compatibility one step back, i.e. you can install it in a 'universal' AGP 2.0 slot, but not in an old AGP 1.0 slot.

Now, in theory any board supporting AGP 2.0 ("4x") should work, and you can identify them by the lack of key in the AGP slot.

In practice, not all cards and not all slots are keyed correctly. For your card it's not an issue (you know it's an AGP 3.0 card, regardless of keying), but for the board, double-check the specification of the motherboard and if they aren't crystal clear, check the chipset specifications too.

The biggest risk is actually the other way round, cards that should have 3.0 keying but instead have universal keying and get inserted into AGP 1.0 3.3V slots and release their magic smoke. Still, better safe than sorry.

Aside from pure smoke generation, be aware that this card is complete and utter overkill for any So370 system and that it doesn't have Windows 98 drivers, so you'll need to run Windows XP on this So370 system and use drivers that are much newer and more bloated than something more period-correct would. That means this card will probably run worse than an older Radeon 9800 or similar, simply because both would bottleneck completely on the CPU anyway, but the older drivers for the 9800 would actually reduce that load. So unless you have a really, really specific use case, this is not a good pairing.

Found a YouTube review, and it's a 1.5v keyed card, and the last gasp of AGP - needs a suitable XP driver set, 10.2 AGP hotfix, and yes, way overkill for a P3, it really needs (ideally) a core 2 AGP board like the 775VSTA, or second choice, a Pentium D motherboard with AGP, or it might be possible to find a S939 A64 x2 with AGP

I have two 3650's on AGP and van conform: these are great for any faster p4 and above. Anything below will be a big bottleneck but on a Pentium 3 board like the CUSL2 it gives image and gets detected. I couldn't actually get it to work for benchmarks...

I had one of these. The Sapphire one, as you. One of the latest (if not the latest) agp cards released and among the 2 or three most powerful.

Thanks a lot for the answers.

Has anyone gotten one of these ATI HD AGP cards working well on an AGP 4x board? I would think maybe an Intel motherboard but most of the other manufacturers had big problems with AGP 4x compliance.