AGP 4x has to do with the number of gaps (?!?)

[Narayan]

A friend of mine told me that you can tell if an AGP graphics card is 2x or 4x by counting the number of gaps it has in the AGP interface connectors. He claims his Creative TNT2 Ultra is AGP 4x, and that so is my G400 DH 32MB, because they have 3 gaps, while AGP 2x cards have 2. Is there any truth in this? I checked an AGP 3D card comparison in a mag, and indeed all the AGP 4x cards had 3 gaps, and all the AGP 2x cards (ATi Rage 128, all 3dfx cards etc.) had 2. Is there any truth in the above?

[Kruzin]

Yes.
AGP4x runs at a different (higher) voltage spec than 1x/2x. In order to make sure a low voltage 2x card is not put into 4x mobos (and thus fried from the extra voltage), they flipped the AGP slot around.

Cards like G400 will fit in either type of board, and auto-adjust to the proper voltage. Older cards (G200, TNT1, etc) will not even fit into the 4x mobos...

[Wombat]

Kruzin has it right, but I wanted to clarify a little.
AGP cards have a gap. It's on one end for AGP 1x/2x cards, and the gap is towards the other end for 4x cards.

Cards like the G400 have both gaps because they are built to use either kind of slot, and can adapt to either voltage.

In the future, you may see AGP 4x cards with only 1 gap because they support only 4x.

[RoGuE]

Originally posted by Kruzin: Cards like G400 will fit in either type of board, and auto-adjust to the proper voltage. Older cards (G200, TNT1, etc) will not even fit into the 4x mobos..

No, any AGP card will physically fit into an AGP 4x slot. Unlike AGP 1x/2x, AGP4x slots have no 'dividers' in the slot.

[This message has been edited by RoGuE (edited 19 May 2000).]

[Narayan]

Wow! I've got an AGP 4x G400!

...but hold on, wasn't there a post a while back that said Matrox 'leaked' AGP 4x cards, and that ALL those cards had a '4' in the S/N? Mine certainly doesn't...

[Snake-Eyes]

Dunno anything about them leaking cards. They specifically made all of their earlier G400 cards to be AGP4x compatible, so that they would operate on an AGP4x motherboard, only at 2x. My G400Max is one such card- it has both slots, and will fit properly in a 4x capable motherboard, but won't operate at 4x, unlike later G400 based cards with the 4 in the part number.

------------------
Ace

[APV]

My Max has a 4A on the model number but PCIlist only say it is 1x 2x card, anyway my motherboard is 2x only so until i change my motherboard, i wouldn't care less. Btw some games sites has pointed out that you will see difference between 1x and 2x but hardly see any difference from 2x and 4x at least for todays games and hardware.