[Leaplist] Need a vid card for a week or so -- don't blow your mainboard AGP slot

[Homer Whittaker]

Thanks Bryan.  I had forgotten about that voltage difference and might 
very well have blown a new motherboard.
Homer Whittaker


Bryan J. Smith wrote:
> I normally wouldn't post to the list, but I don't want anyone to blow
> their mainboard's AGP slot.
> 
> You see, there are different voltages for AGP cards and mainboards
> that apply to AGP 1.0, 2.0 and 3.0.  I have personally fused AGP pins
> in a slot by using an old AGP 1.0 Matrox G200 in AGP 2.0/3.0
> mainboard slots, ruining my AGP slot.  The Matrox G200 attempted to
> draw 3.3V from the slot which could only provide 1.5V and bam, that
> was that.  I was lucky the whole mainboard wasn't ruined.
> 
> As such, one needs to be extremely careful not to use a 3.3V AGP card
> in an only 1.5V capable AGP slot mainboard, or the mainboard will be
> ruined.  Going the opposite, using an 0.8V AGP card in only a 1.5V
> capable AGP slot mainboard will probably ruin the AGP card, or in the
> best case, it just won't work (if the card has some safety logic). 
> I've seen the latter happen to people personally as well.
> 
> I documented the different AGP 1.0, 2.0 and 3.0 specs and voltages
> here:  
> http://thebs413.blogspot.com/2005/11/agp-agp-pro-pci-and-pci-x-voltage.html
> 
> They still vary, as 1.0 is 3.3V, 2.0 is 1.5V and may be 3.3V tolerant
> (optional) and 3.0 is 0.8V and may be 1.5V tolerant.  One of the
> reasons I still keep my 3.5 year-old GeForce 6800GT is because it was
> an AGP 3.0 (0.8V) card with 2.0 (1.5V) tolerance, unlike most "8x"
> (3.0) cards produced in the last 3 years.
> 
> So _take_care_ to check those old AGP cards when you give them away. 
> The newer Athlon 64 mainboards with AGP are going to be 3.0, and may
> only support 0.8V or, optionally, 1.5V.  If you throw an old 1.0/3.3V
> or even a 2.0/1.5V card in there, you may blow the mainboard.  So,
> what AGP cards are you offering?
> 
>