To SLi, or not to SLi?

[ChronoCabal]

Hello guys! My system setup is this:

CPU = AMD Phenom II 955 X4 Black Edition 3.2Ghz
AM3 Motherboard = ASUS M4N82 Deluxe (PCI-E, Tri-SLi)
RAM = 6GB Corsair 800MHz PC2-6400 DHX
PSU = Avenge Power 850w
Current Video Card = Gainward GTX460 GS 2024MB.
Chassis = Raidmax Sagitta
OS = Windows 7 64Bit
HDD = 750GB SATA
Monitor = Samsung P2370HD in 1920*1080

It currently runs everythng I throw at it rather well- Crysis 2 runs at 30fps min 45 avg, Portal 2 55-60fps, Mass Effect 2 60fps, Starcraft 2 30 min 60 max, all maximum settings. I'd like to try and pick up the minimum gps in the likes of Crysis 2, and can get a Gainward GTX460GS 1GB second hand for £100.

I have a few questions though- if I SLi the two cards, will the 2GB of my current one and only 1GB of the second cause any issues? I'd assume I would have 3GB of total graphics memory available to me- but if the two cards are otherwise identical- will they still run at full pelt together?
Also, will my PSU be powerful enough? It's a 80+ rated one, and although it's not a big name brand- it's been fully reliable so far. I think I read somewhere that the 460 sucks around 110w under load?

Finally- is this actually worth doing? Whilst it runs most things fine currently- I'd like to be able to future-proof it for a while to come- certainly until the next full rebuild anyway! Opinions welcome!

Lee

 

[Mjolnir]

No, assuming they work together, you'll only get the lower cards memory, I.E. 1GB. You don't get a combined VRAM between multiple cards. (EG, if you have 3 GTX 580's in SLI, thats 1.5GB each, so 4.5GB right? Nope. Only able to use 1.5GB. It doesn't scale that way unfortunately..

Your PSU wattage wise would be fine.. But I've never heard of it so...

If you can get a 460 for cheap, sure.. But for a single monitor solution at 1080p, I'd say save up some and upgrade completely to like a GTX 570/580. For a single monitor 1080p res, you don't really need an SLI setup. But it's personal preference so..

 

[Ethan E]

IF, and its a BIG IF, you can get the two cards to work together, they will only "see" 1gb of ram. NVIDIA states that the GPU and VRAM need to be identical to run in SLI. Cards from different manufacturers can be used, but they must be the same GPU and VRAM. So you could get another 460 GS 2GB fron any manufacturer, but I have serious doubts that a 1GB card would work at all.

 

[JeremyCT]

Ethan's right, nVidia states the cards must match entirely in terms of specs to work in SLi. I doubt that setup would work.

Since you don't need it right away, wait for a card that matches your 2GB original to come up for sale. You'll have fewer issues.

 

[RADIO_ACTIVE]

If it is running everything you are playing fine and you are happy with it, why not just wait till the next series of cards come out and then decide what to do. It will give you more time to save up and buy a better card.

 

[EarthDog]

dont SLI for 1920x1080. 460 1GB should play things well at that res, so get a single card.

 

[ChronoCabal]

Wow - thanks for the opinions guys - look like a overwelming vote for sticking with the single card!

I'll save up for a 580ti or similar then, and enjoy the 460 for the time being!

Lee

 

[PeterPwned]

580ti? As far as I am aware that card does not exist. If you mean a 560ti, that would not be a major upgrade in my opinion. I feel that saving and buying a 570 if you find the 460 is not good enough might be a good idea.

 

[Radioactivaa]

No, I dont think its worth it, as long as it runs everything, and you dont feel like you need more power. I would wait and maybe upgrade to a 5 series card.

 

[PeterPwned]

On the other hand a 460 is stunningly cheap and it must be said that Evga is making 460 2Win cards (2 460s on one card) that are supposedly faster than a 580. So yes, I believe you will get quite a bit of performance by adding a second card, but then thats about it with upgradability of your rig.

 

[Starlo]

+1 for getting another cheap GTX 460 and going the SLI route. Why? you get great scaling performance which means it will perform as well as a GTX 570 or maybe even a GTX 580 for a 1/4 of the cost.

 

[PeterPwned]

Don't forget that you can then instead of getting a second 570 or 580 just afford to buy a Geforce 600 or 700 card that beats 570/580 SLI, just saying.

 

[ChronoCabal]

So- trying to find a cheap second 2gb Gtx460 is still a good idea for now then? I've not had much experience with SLi (I had 2 7800GTs 255mb back in the day lol), so my main point still stands as to wether it's worth doing. I paid £150 for my current 460, so I figured that if I could get another one for a similar price, I'll have a good whack of GPU performance for a decent cost. Or maybe I should look into OCing my 460 instead..?

 

[Kozo]

Chrono you could also OC and SLI for a really nice boost. Only thing I would like to mention about going the SLI route is that on rare occasions SLI can be an issue. I had a couple gts 250s in my rig a while back and I always had problem with horizontal screen tearing esp in the bottom half the screen. After begging and borrowing other cards and bridges I found that for some reason those cards didn't like each other.

In your situation though I would still recommend another 460. Great scaling. Add in OC and you will be set for a while.

 

[ChronoCabal]

Thanks for all the replies! Would a Palit Sonic GTx 460 2GB be compatible with my Gainward then? I read somewhere that Palit actually own Gainward and are essentially the same..

My Gainward: http://www.google.co.uk/m/products/...84987513138987367&hl=en&ptab=o&postart=0&sa=N

The Palit Sonic: http://www.google.co.uk/m/products/...+sonic+460+gtx&hl=en&cid=6796252284756523532#

Google lists both the clock speed (700mhz, 725mhz,) and Memory clock (1.8ghz, 3.65ghz) being different- Would this cause any problems in SLi?

T

 

[RADIO_ACTIVE]

Wow - thanks for the opinions guys - look like a overwelming vote for sticking with the single card!

This is because there is nothing really pushing the hardware at that reso unless you are running a 3D setup, a single 460 can handle almost every game at that resolution paired with a decent CPU. Thank you consoles and DX 9 for sticking around

 

[Zantal]

Google lists both the clock speed (700mhz, 725mhz,) and Memory clock (1.8ghz, 3.65ghz) being different- Would this cause any problems in SLi?

one of those is an overclocked version of the card (do not take. Mild overclocking is easy stuff these days) the huge memory discrepancy is because nobody really knows which value to post. some post actual memory bus frequency others mention the actual transfer frequency (sending 2 bits per clock or for gddr5 4 times per clock).

 

[ChronoCabal]

Ah - I did wonder if the memory clock was a discrepancy. Of course my question still stands.. will it work, do you think?

The reason I ask about the Palit is because there is a cheap one going on eBay UK at the moment - so I'm tempted!

 

[Ethan E]

Different clock speeds should be fine as long as the GPU and VRAM are the same. You can always overclock the slower one or (gasp) downclock the faster one to make them match.

 

[JeremyCT]

I'm pretty sure the clocks do need to match. Easy to accomplish via a BIOS flash after some testing to find the highest stable frequency for each card.

And yes, I would test card's overclocking ability individually. Go with one step down in clocks from the lower of the stable clocks between the two (does that make sense? hope so) to make sure you don't overstress the "less stable" card and you should be golden. With a little luck they'll both be stable at the same speeds and temps and you'll be a happy camper with a very fast setup. I hope your power supply is up to the challenge.