jm7 said:
I hope someone can explain what is happening on the following config:
I have an IBM Thinkcentre m55 (Core Duo 1.86 with 2Gb RAM) - it has an
onboard video controller. This machine does NOT have a PCI-EXPRESS 16 slot.
I needed to run a 3D application so I got a PCI (old standard) NVIDIA FX5200
card.
The 3D graphics features now work BUT EXTREMELY slowly. Is this because
when doing 3D it is going through the SLOWER PCI bus?
This IBM only has one PCI and one PCI-EXPRESS 1 slot on a riser.
I wonder if it is possible to get a riser card with a PC-EXPRESS 16 slot on
it?
Thanks in advance.
First of all, they aren't going to put a PCI interface on a powerful
card. That is why you see cards like FX5200 and FX5500. On the Newegg
page, the X1550 with PCI, is probably the fastest thing there. (There
are some FireGL cards, but there you are paying for a certified OpenGL
driver.)
If you had a PCI Express x1 slot, that is 250MB/sec bidirectional,
versus the 133MB/sec unidirectional of the PCI bus. That means the
PCI Express x1 slot is more useful than the PCI bus slot, but not by
a lot.
But how demanding is your application ?
People certainly have managed to play games on a PCI FX5200,
but obviously not many games are going to be able to run on
more than the minimal detail settings.
As for PCI Express x1 cards, I see five listed here, and not
all of them are low profile. A couple of them are quads and
expensive. Some don't come with the necessary low profile
faceplate. The HIS one is a dual slot width card, which may
or may not be an issue. (You'd have to check the slot layout
of the computer motherboard, to see whether it would fit, or
bump into some other card.) NVS285 is classed as "professional 2D"
in an HP document. So there is not a lot of real choice here.
http://www.newegg.com/Product/Produ...E&N=2010380048 1069620108&bop=And&Order=PRICE
The ATI 1550 is a rebadged 1300. In the chart here, there
are several X1300 models near the bottom. The FX5200 would
be maybe half or less, of the least performance on the
chart.
http://www23.tomshardware.com/graphics_2007.html?modelx=33&model1=739&model2=740&chart=285
So while the X1550 might be an improvement, it won't be
worth the money to upgrade.
If you want serious horsepower, get a computer with
a PCI Express x16 slot. The single biggest mistake people
make, buying Dell/HP/Gateway etc, is picking the cheapest
machine, the one that has no proper video card expansion
slot. And it is not like the manufacturer is going to be
honest, and say "look, this machine is crippled because we
saved $5 by removing the video card slot, and you'll
soon regret buying this". If you were a relative, I would
take the components out of your computer, buy an adequate
motherboard, a retail copy of Windows, a new computer case,
and just... fix it.
To see the impact that variations in bus bandwidth make, the
authors of this Tomshardware article taped and insulated various
numbers of PCI Express lanes. They ran benchmarks with
x1, x2, x4, x8, and x16 lanes enabled. How much an application
feels the effect of limited bandwidth, really depends on how
much raw data has to be pushed across the bus.
Notice how some games work just fine when starved...
http://www.tomshardware.com/2004/11/22/sli_is_coming/page10.html
SPECviewperf, on the other hand, really feels the effects...
http://www.tomshardware.com/2004/11/22/sli_is_coming/page8.html
Paul