Which card for dedicated physx?

[Kreatos]

I have narrowed down my decision to two cards.

GTX650ti or gt 640

i can get a great deal on both but the gtx650ti will cost double the gt640.

I can not find enough benchmarks or test videos to choose. I know the specs and yes the 650 ti is much more ....well everything than the gt640; however will the 650ti just
be overkill and i wouldn't be able to tell the diff anyway?

Remember, I am talking about DEDICATED physx.

 

[Azn Cracker]

What is your main card? It really depends, but i would think the 650ti is a better choice. The gt 640 sucks.
Getting getting a low end card for physx can actually be slower than a single card.

 

[Kreatos]

well, i am adding one of these cards to achieve physx support in my amd build. i posted a similar question last week about adding in the 650ti and the two responses were to sell my hd7850 and go all nvidia 650ti's or 660's. but i am on a 150 dollar max budget and want to keep my set up but have physx support.



MSI 970A-G46 MOBO
AMD FX-6100 OC'd to 4.05 ghz
16 Gb Gskill ripjaws 1600
2x500 Gb Seagate HDD
1000 Watt Antec Psu
Antec 900 case with 5 case fans
2xDVD burner
1680x1050 res monitor

GPU: XFX HD7850 2Gb

 

[17seconds]

Check the CUDA cores on the 640 vs. the 650. If they are the same the PhysX performance should be very similar (depends on OEM versions vs. retail, Ti vs. non-Ti, etc.). Clock speed may play a small role, but the CUDA core count is most important. It may be that the 640 will do just fine if the CUDA core count matches up with the 650.
http://1pcent.com/?p=169

Edit: After reading your post more carefully, it appears you are choosing between the 650 Ti (768 CUDA cores) vs. the 640 (384 CUDA cores). The 650 Ti, as shown in the link above is significantly better, but the question is whether its enough to justify the higher price. I'm guessing the answer is no, but you should also consider the 650 non-Ti for a cheaper alternative.

 

[Kreatos]

i have a gtx 285 1gb card i use with my hd7850 but i need that card for a separate build i use at work. the 650 ti has double the cuda cores as the gt640 and so doubles the price.

but , i was looking at the specs of my gtx 285 1gb and comparing the three:

GTX 650 Ti = 768 Cuda Cores
GT 640 = 384 Cuda Cores
GTX 285 1Gb = 240 Cuda Cores

yet as far as hardware compare shows the gtx 285 over powers the gt640 theoretically

http://www.hwcompare.com/12896/geforce-gt-640-ddr3-vs-geforce-gtx-285-1gb/

I am trying to understand. but i see more cores on the gt640 and much higher core clock too. why does the gtx out do the gt?

 

[Kreatos]

http://www.anandtech.com/bench/Product/612?vs=520

this says the same thing

 

[bigshootr8]

You will need to get a hacked driver to use both a AMD and Nvidia card in tandem with Physx a while back Nvidia locked the ability to do so.

 

[Kreatos]

You will need to get a hacked driver to use both a AMD and Nvidia card in tandem with Physx a while back Nvidia locked the ability to do so.

I have already done this before with the gtx285. With the patched or hacked driver whatever you want to call it.

 

[bigshootr8]

Yea, the 650Ti is the pinnacle at the moment of a dedicated physx card anything beyond it is wasted. A 650Ti has quite a bit more performance then the 640 and with regards to physx I believe the cuda cores have more of a impact on things and that is the huge difference with regards to physx and the 650Ti versus the 640.

 

[Kreatos]

That is what i thought. But why does the gtx 285 out perform the gt640 if more cores and higher clocks =better?

 

[bigshootr8]

Because of the 2nd number keep in mind that its ever so telling with graphics card the 2nd number in a series of cards. The 640 is a more modern card with new tech, however, the 285 is a workhorse cards the 6,7,8 series cards from nvidia have always been the statement of the entry, to high end gaming with the 5 getting you a little bit into the game.

 

[doubletake]

I am trying to understand. but i see more cores on the gt640 and much higher core clock too. why does the gtx out do the gt?

Because they are two entirely different architectures. You cannot directly compare shader core count between GT200 and GK107.

 

[bigshootr8]

Well that as well but newer tech doesn't necessarily mean faster.

 

[17seconds]

That is what i thought. But why does the gtx 285 out perform the gt640 if more cores and higher clocks =better?

You're confusing graphics performance versus CUDA compute performance. The 285 can do DirectX 10 graphics better than a 640, but it is not near as capable when it comes to PhysX calculations.

 

[Kreatos]

Would i be able to tell a difference from the GT640 vs GTX650ti strictly for physx performance when added to my HD7850?

 

[bigshootr8]

I found this for borderlands 2 with the GTX650Ti

http://www.ninjalane.com/reviews/video/gtx-650ti_roundup/page7.aspx

and the GTX640.
http://1pcent.com/?p=135

 

[bigshootr8]

Looks like either are pretty solid choices actually.

 

[Kreatos]

i have skimmed over that ppu shoot out post many times but i just wanted to do my homework and get other opinions first.

so just for my knowledge, graphics performance and cuda calculations for physx are different. i thought that was the case but i never like to just assume.

 

[Kreatos]

Best answer selected by kreatos.

 

[bigshootr8]

The way I normally go at it is this. If you have a current gen card and you are playing a brand new game that uses physx typically they will recommend a previous gen card. For example when batman arkham city came out they recommended a 570 paired with a 460 as a dedicated physx card with high physx settings. So you could apply the same logic here. If you had a 600 series card a 500 series card would probably be the recommendation now. However same generation card you could geta way with a 4/5 series gpu but come the next gen cards you may want something like a gtx770+gtx660 or a equivalent AMD card plus hacked driver.