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ir123
06-11-09, 09:04 PM
What is the effect of putting a PCIe 2.0 video card on a PCIe 1.0 motherboard? Is the clock rate, memory rate or bit size supposed to be reduced?

CaptNKILL
06-11-09, 09:47 PM
It will just fall back to PCI-E 1.1 mode (most systems are 1.1, not 1.0).

PCI-E 2.0 x16 has twice the bandwidth of 1.0 or 1.1 x16 and supplies more power through the PCI-E bus.

I don't think it makes much of a difference in most cases, though that will change as graphics cards get faster.

Also, PCIe 2.0 will be faster than 1.1 in SLI and Crossfire setups because the cards are actually sending data between each other over the PCI-E bus, where as a single card doesn't need to do this.

ir123
06-12-09, 07:46 PM
I see, but what about the clocks that I mentioned? For an old system that is PCIe 1.x I bought a card that is supposed to have memory at 1400MHz but the nvidia-settings say it's only 700MHz. So I just want to make sure it is the lesser PCIe version that is to blame, or perhaps something else on the PC. Is there some lower-compatibility mode on lower motherboard or perhaps insufficient power supply that would cause this effect or was it false advertising?

CaptNKILL
06-12-09, 07:50 PM
PCI-E has nothing to do with the clock speed or any other specs of the card.

Most likely your card is down-clocking in 2D mode to conserve power and lower temperatures. Most cards from the past 3-4 years have done this.

ir123
06-12-09, 08:00 PM
Do you mean powermizer? So the performance levels on the powermizer tab don't display the max, just the current clocks? Would nvclock give the real specs, or maybe another tool?

For instance, what exactly does this mean?:
---------------------
Version: 62.92.5e.00.00
Signon message: ASUS EN9600GSO VBIOS Ver 62.92.5E.00.AS09
Performance level 0: gpu 550MHz/shader 1375MHz/memory 700MHz/0.00V/100%
VID mask: 3
Voltage level 0: 1.05V, VID: 0
Voltage level 1: 1.15V, VID: 1
Voltage level 2: 1.25V, VID: 2
Voltage level 3: 1.35V, VID: 3
-------------------
1375MHz/memory 700MHz/0.00V/100% ?

Also I don't see any change displayed whether I'm running 3d or not.

B0ne
06-12-09, 08:47 PM
I see, but what about the clocks that I mentioned? For an old system that is PCIe 1.x I bought a card that is supposed to have memory at 1400MHz but the nvidia-settings say it's only 700MHz. So I just want to make sure it is the lesser PCIe version that is to blame, or perhaps something else on the PC. Is there some lower-compatibility mode on lower motherboard or perhaps insufficient power supply that would cause this effect or was it false advertising?

It says its 1400mhz because it sort of is, but isn't; it uses DDR memory which is where data is transferred at both ends of the clock cycle, in simple terms the memory operates at double the speed its actually at, so it is 700mhz but doubled because its DDR.

I hope that makes sense haha

ir123
06-12-09, 08:50 PM
I see, thanks, so it is the standard spec exaggeration. Live and learn.