Regarding MoBo with 4x PCIe

[cvitanic]

Hi, maybe someone can shed some light on this issue. I want to upgrade to PCIe graphics card, but I currently have a 478 P4 3,2 HT CPU, which I don´t want to upgrade yet.

The only MoBo available here is the P4V800D-X from Asus, which has an AGP and also a PCIe slot, but the specs show that such PCIe port doesn´t work at 16x transfer rate, but 4x instead.

My question is if I´ll be able to use a high end graphics card (nVIDIA 7600 or 7900) without losing much performance, as I don´t know if these GPUs fill the 16x PCIe bus bandwith.

Anyways, it seems to be the only option to replacing the whole system including MoBo, CPU and Graphics Card...

 

[TheTallGuy]

You could use it, but it won't work to it capabilities. The rest of your system is going to be the limit your speed. You'd be better off getting a cheaper AGP card because you'll see the same performance.

 

[cvitanic]

You could use it, but it won't work to it capabilities. The rest of your system is going to be the limit your speed. You'd be better off getting a cheaper AGP card because you'll see the same performance.

According to this theory, Which would be the bottleneck ? If the CPU is working at 200 MHz bus and the memory throughput is DDR, therefore 400 MHz; I understand that PCIe doubles the current PCI transfer rate which is 66 MHz, so we have a theorethical throughput of 133 MHz on PCIe.

I just don´t see how the rest of the system could be limiting the performance of the PCIe bus and the PCIe video card.

 

[hella-d]

Suggestion...... 7800GS And A New Heatsink To OC That CPU

 

[cvitanic]

Suggestion...... 7800GS And A New Heatsink To OC That CPU

That´s something I had thought of as well, bu t I´ll still be stuck with AGP, besides the 7800GS AGP doesn´t come cheap.

Now, another factor for switching MoBo is DDR slots as now I only have three and I was running 1,5 GB but not Dual Channel, so I removed 1 stick. Now I need a 4 DIMM slot MoBo plus another 512 MB stick to run 2 GB Dual Channel.

BTW, I have a Thermalright XP90 so I OC to 3,45 GHz. Any ideas how far I can go with this heatsink without losing stability ?

 

[MrCommunistGen]

As far as I can tell from the Asus website that board has a 16x PCI-E bus. They claim it has 4x the bandwidth of 8x AGP, but thats only if you combine the upstream and downstream bandwidth of PCI-E since in AGP they are shared. You can probably use any card you want to with that board.

Edit: Aww crap... nevermind. 16x slot, 4x bus. My guess is that it will still perform pretty well with all but the highest end cards. I remember reading an article when PCI-E first came out where people benchmarked 16x cards with the bus restricted to 8x, 4x, and 1x (I think). It may have even been here on Toms...

Edit2: Yup it was a Tom's article. At least for gaming 4x seems to be more than enough.

-mcg

 

[cvitanic]

As far as I can tell from the Asus website that board has a 16x PCI-E bus. They claim it has 4x the bandwidth of 8x AGP, but thats only if you combine the upstream and downstream bandwidth of PCI-E since in AGP they are shared. You can probably use any card you want to with that board.

Edit: Aww crap... nevermind. 16x slot, 4x bus. My guess is that it will still perform pretty well with all but the highest end cards. I remember reading an article when PCI-E first came out where people benchmarked 16x cards with the bus restricted to 8x, 4x, and 1x (I think). It may have even been here on Toms...

Edit2: Yup it was a Tom's article. At least for gaming 4x seems to be more than enough.

-mcg

Thans for that link ! It really cleared out a few things regarding the PCIe transfer bandwith. I think I´ll give that MoBo a try, so I can stick to my 478 P4 and my GF6600GT while I choose a better card.
Thanks again !