"Steve Smith" said:
Thanks for the reply Paul,
My card is one of the universal AGP type. However does this mean it will
operate at both 3.3v and 1.5v?
Steve
The motherboard provides the power. In a "tie breaking" situation,
the graphics card specifies its preference via the TYPEDET pin.
If the motherboard has a preference, and the graphics card is
universal, the motherboard will use whatever it wants. Since your
card is universal, it is not going to matter which policy applies,
they'll just do the right thing.
One thing to watch for with the AGP rates, is while ideally, a
motherboard should support all rates AGP 1X,2X,4X,8X, in fact
some of the newest Northbridge chips have some limitations.
For AGP 3.0 standard, the supported rates are 8X and 4X, at
0.8V. (The 0.8V is really running off a 1.5V supply, but the
signals sent on the bus are 0.8V high, so a 0.8V card is
comfortable with 1.5V motherboards, as it is all really
based on 1.5V.) The AGP 3.0 standard doesn't say that 2X and
1X have to be supported (if, say, the card only wants to
use the 0.8V signalling option).
For AGP 2.0, a 1.5V card should be supporting 4X, and for
backward compatibility it should do 2X and 1X as well.
Not all Northbridges now support both versions of the spec.
For example, one I was researching the other day, did
8X, 4X, and 1X. The 2X was missing, implying that the
Northbridge in that case really wasn't AGP 2.0 spec
compatible.
Now, why would you, as the owner of a 4X video card, care ?
The fun begins if you are having trouble running your
new motherboard and video card at 4X. Someone would give
you the advice, to run the card at 2X instead. But if the
Northbridge doesn't support 2X, then the crappy option of
running at 1X rate is all that is left.
As a consequence, I recommend that you download the manual
from the Asus (or other manufacturer's site), and check
the BIOS portion of the manual, to see what options the
BIOS has for AGP rate. This advice is just insurance, in
case the AGP isn't stable on your new board, and rather
than RMA the motherboard or replace the video card, you are
happy enough to just adjust the AGP transfer rate. There
isn't much practical difference between AGP 2X and AGP 4X
transfer rates.
I would give advice on chipsets, but the thing is, the
crappy chipsets have a 3% return rate, while the good
chipsets are much less than that. So, you are quite likely
to have a good working system in either case. The happy
motherboard owners don't post here
If you decide to buy an A7N8X family board, I recommend
you spend $25 and get a BIOS Savior to go with it. There
is a bug in some of the boards, where reflashing the BIOS
will recover the board after the screen goes blank. The
backup BIOS chip on the BIOS Savior means not having to
RMA the board (
http://www.ioss.com.tw). Otherwise, Nforce2
boards are a good choice (even an Abit NF7-S would be
good).
HTH,
Paul
