9400GT/9500GT For PhysX?

[The boy 4rm oz]

During one of my daily ventures across the internet I ran into some cheap 9400GTs ($62.00AUD for 512mb $83.00AUD for 1GB) and 9500GTs ($79.00AUD), then I got thinking.

Currently I am running an 8800GTX which is running both graphics calculations and is also doing physics calculations. I went on the Nvidia website to get a better look at the 9400GT and 9500GT specs and yep they both support CUDA and PhysX.

With my 8800GTX a little behind the ball (still damn fast though) and with newer games demanding more (physics and graphics wise) I was just wondering if it would be possible/worth getting one of these cheaper cards to run the PhysX calculations and free up some more clocks for my GPU. I know it is possible to get a card like this to do the PhysX calculations, I have seen it done before.

I have been thinking and there are a few issues I can see.
A Downgrade:
Will a 9400GT or a 9500GT perform worse for the PhysX calculations than my 8800GTX?
Power:
Currently my system (see system specs) is running off a Antec Neo He 550W PSU. This PSU runs great, it's quiet and powers my extra fans and CCFLs that are in LEXA. I will be adding an Auzentech Xplosion Cinema 7.1 audio card soon which shouldn't be a problem for my PSU and later on I will be adding an extra HDD. By adding an extra graphics card will I overload my PSU or should it be ok? Nvidia rate the cards as using 50W of power max and only needing a 350W PSU. I think ATM I am only using around 400W of power (according to the PSU calculator, calculated a long time ago lol) so I think it should be ok but I'm not sure.
Choosing The Card:
Which card to chose, the 9400GT 512Mb/1GB or the 9500GT 512Mb? The 9400GT has half the processor cores of the 9500GT (16 compared to 32) but the 9400GT comes in a 1GB version. The 1GB version of the 9400GT costs just a little more than the 9500GT. Would the extra RAM help in the PhysX calculations or will the extra amount of processor cores be more powerful. What would you chose?

As it stands I have no idea which card to chose nor do I have any idea whether it would be worth it in the long run or not. Any insight would be greatly appreciated.

Tb40

[The boy 4rm oz]

Oh In case you guys were wondering, these are the cards I was looking at.
Gigabyte 9400GT 512MB:
http://www.gigabyte.com.tw/Products/VGA/Products_Overview.aspx?ProductID=2897
Gigabyte 9500GT 512MB:
http://www.gigabyte.com.tw/Products/VGA/Products_Overview.aspx?ProductID=2879
ECS 9400GT 512MB:
http://www.ecs.com.tw/ECSWebSite/Products/ProductsDetail.aspx?detailid=921&CategoryID=5&DetailName=Feature&MenuID=54&LanID=0
ECS 9400GT 1GB:
http://www.ecs.com.tw/ECSWebSite/Products/ProductsDetail.aspx?detailid=922&CategoryID=5&DetailName=Feature&MenuID=54&LanID=0
ECS 9500GT 512MB:
http://www.ecs.com.tw/ECSWebSite/Products/ProductsDetail.aspx?DetailID=927&CategoryID=5&DetailName=Feature&MenuID=54&LanID=0
ASUS 9400GT 512MB:
http://au.asus.com/products.aspx?l1=2&l2=6&l3=790&l4=0&model=2678&modelmenu=1
ASUS 9400GT 1GB:
http://au.asus.com/products.aspx?l1=2&l2=6&l3=790&l4=0&model=2677&modelmenu=1
ASUS 9500GT 512MB:
http://au.asus.com/products.aspx?l1=2&l2=6&l3=760&l4=0&model=2709&modelmenu=1

I was hoping to find a card with Black PCB but no luck, blue will have to do, it's close enough. I am leaning towards the Gigabyte cards or the ASUS cards. The Gigabyte cards have good stock coolers as do the ASUS cards but the ASUS 9500GT has an exceptionally good stock cooler, very big and very quiet. The ASUS 9400GTs are also half depth which is a bonus.

I am leaning towards the ASUS cards if I get one but they do have a higher price, the 1GB 9400GT is about $25.00AUD more expensive than the 9500GT.

[crenn]

In this case, more cores will help with your calculations, make sure it's GDDR3 RAM though. 512MB is more than enough for PhysX. If you can afford it, try for a 9600GT (or a 9800GT if you can have a little more cash to burn) to use as a PhysX card. Remember, PhysX has limited support and as far as I can remember, you have to have a 2nd monitor (or the same monitor with a different connection) plugged into the PhysX card if you're running Vista. This may have changed.

[The boy 4rm oz]

Thanks for the info crenn. I was looking at the 9800GT but it requires a dedicated 6 pin power plug which I don't have nor do I have the spare Molex plugs for the adapter. The 9600GT is an option but it costs an extra $65 over the 9500GT. I will look into it and see if I can find some different cards. All the cards I listed above only had DDR2 RAM but I think the 9600GT uses DDR3 by default.

EDIT:
The 9600GT also requires dedicated power so that rules it out. Looks like the 9500GT is the best option for me, I will see if I can find a DDR3 version.

[crenn]

Just remember that the P100 had 40 cores I believe.

[The boy 4rm oz]

I know the 9600GT is a much better card than the 9500GT but I can't physically run it without a PSU upgrade which I don't want to do, I would have to pull apart every inch of LEXA :(.

I might wait for a bit before making up my mind. If you have any extra info it would be great.

[crenn]

The only thing I can think of is, if you want to get this card to act as a PhysX enabled card, I'd suggest seriously looking at what games support GPU PhysX and how often you play them.

[The boy 4rm oz]

That is a good point. I was thinking more for newer/future games, not the older games I play. I will check the list now and have a look.

[The boy 4rm oz]

I just found this on the Nvidia web site:
http://www.slizone.com/object/sli_cuda_learn.html
The configuration I am looking at is possible and has just been introduced. I thought it was rather new because I saw a Tri-SLI GTX280 running a 9800GT for PhysX.

Out of the partial list of PhysX enabled games found here (http://www.nzone.com/object/nzone_physxgames_home.html) I only play/have 3 of the titles (AoE III, GRAW and UT3). However they say they will be adding more titles through patches and are signing up and coming games to implement the technology. I will see if I can find a more complete list of games.

[crenn]

It was suggested when GPU PhysX was first introduced. Note that some CPU PhysX titles can offload PhysX to the GPU even if it's not on that list (I-Fluid is one I believe). However, the list of titles from that website should be fairly complete and some will be compatible with GPU PhysX.

[The boy 4rm oz]

I think I may as well go for it. GPU PhysX will be more widely spread in newer titles and be supported through patches for some older titles. At $80AUD for an 9600GT it's not a major expense.

Now all I need to worry about is whether my PSU will have enough wattage to run a sound card an extra HDD and the 9600GT.

[crenn]

Don't you mean $139 for the 9600GT.

[The boy 4rm oz]

I actually meant the 9500GT. $79 for the 9500GT.

[The boy 4rm oz]

Well I may be able to pick one of these cards up tomorrow when I am in town, depends if I get paid or not. I hope my PSU will have enough head room for the extra card, it only uses 50W of power so hopefully I will be ok.

I may just give it a miss altogether for the time being .The technology is still young and I want to find out exactly how much power my rig is sucking before adding an extra card.