AGP compatibility

Video, SCSI, modem, CDROM/CDR/CDRW, etc.
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djwhite
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I would like to change my configuration to P4 DDR. In addition to that I need new motherboard :). But I would like to keep my old GPU ASUS V7100 GeForce 2MX 400 64Mb + TV out. What is a question? Can I put my old GPU in AGP slot with only 1.5V support power supply? I have chosed one of these motherboards: ASUS P4B266-SE or MSI 6398 (845D) Ultra ARU. Both motherboards support only 1.5V AGP GPU. I think my GPU is compatibile with both standard 1.5V and 3.3V but I am not sure. Need quick answer. Thanks in advance.
soupy
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It looks to me like 4x AGP cards are notched a specific way. I think your card should work, but using a GF2MX with a P4 is a serious bottleneck.


Question :

My P4B ran out of order suddenly with my SiS305 AGP card. It was just working fine before I replaced the other AGP4X card. What happened to my P4B?

Answer :

Intel 845 chipset supports 1.5V signaling AGP cards only and the AGP slot on P4B got 1.5V key in it following the AGP specification in order to prevent a 3.3V AGP card from being plugged in. However, it turned out some AGP adapters such as SiS305 based cards, though operate at only 3.3V signaling level, were notched at the 1.5V key on the golden-finger interface. When using these cards, if the Vddq and VCC3.3 signals are shorted on them, will break up the 82845 memory controller hub as the Vddq is raised from 1.5V to 3.3V instead. In other words, the P4B mainboard will be permanently damaged as a result as soon as the system is powered up with such an AGP card. According to AGP specification, AGP4X mode will work at 1.5V signaling level only. If your AGP card has the 1.5V notch as illustrated in the user's manual but it cannot support AGP4X, please check with your card provider or manufacturer whether it can operate at 1.5V signaling level before it's used in combination with P4B.
Flash your BIOS at your own risk.
djwhite
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Joined: Fri Apr 19, 2002 9:24 am

Thankk You Soupy. I allready send question to ASUS but they did not ansver me yet. About Yours sys850 GPU there is in the manual of ASUS p4b266 motherboard that You could not use that chipset sys850 becouse it works only on 3.3V AGP basis.They did not say anythink about my GPU. But there is software ASUS SmartDoctor for monitoring of GPU. On my motherboard (old MSI 6151 BX440) there is on display: AGP Bus VDDQ Voltage: 3.36 and AGP BUS 3.3 Voltage: 3.36. Status: Your VGA Card is OK. But there is in the manual for ASUS SmartDoctor example:AGP Bus VDDQ Voltage: 1.49 and AGP BUS 3.3 Voltage: 3.36. Status: Your VGA Card is OK. And that's the reason I think it will work. If the card is only 1.5V AGP it would be burn down allready. But it works normal for 6month. Am I right?
djwhite
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When I tallked about Yours card I sow it in the ASUS manual I mean sis305 AGP not sys850. Sorry.
soupy
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Now, I don't have an i850 motherboard, so I'm not speaking from experience. But from what I read, it looks like the SiS 305 is the only card that has the problem.

It looks like every other 4x AGP card should be ok, but if I were you, I'd try to make sure.
Flash your BIOS at your own risk.
djwhite
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Joined: Fri Apr 19, 2002 9:24 am

I received e-mail from ASUS.ASUS V7100 video card can support both 1.5v and 3.3v voltage specs and it can change to the correct voltage according to the AGP slot in the motherboard automatically.
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