SLI

[LSPIII]

Hi guys, I have just managed to acquire myself a second 7800GTX which I plan on running in SLI. Got a good deal on it. Is there anything I should be thinking about?

I will be runnning it on the Asus A8N-SLI Premium, so I know that the second PCI-E slot isn't the full 16x. I run XP x64 and have the latest drivers from the nVidia website already. Is there any games out there which could have an issue etc. Really, I'm just looking for some info on it!

Cheers

 

[Ronaldo]

both pcie are x16 but if u sli cards they run at x8 but you wont notice any difference between 2 7800 in x16 slots to x8

make sure you got good psu and a good working bridge for the cards

 

[LSPIII]

make sure you got good psu and a good working bridge for the cards

I have literally just opened the static bag containing the bridge that came with the motherboard so that should be fine.

Power supply... How do I put this... Bear trap... Sounds about right. Fell in to a bear trap by purchasing the Hiper Blue and now belong to the Hiper-Explosive club. It's been fine apart from the one failing on me. Decent voltages on all rails. I hope it can handle the extra load. I have managed to reduce my hard drive count by 3 in preparation so that should help.

 

[pastymuncher]

A pair of 7800GTX's will stress that Hiper out. I had one blow with a pair of 7800GT's on it. That took out the motherboard. I would seriously consider selling it and getting a decent psu. Hipers are not capable of outputting their claimed 580w either.

 

[MuSsEr]

i was running SLI 7800's in my hiper 580...it blew up
but then again my m8 had the same psu but was only running a 6600gt and it did exactly the same as mine...3 weeks apart, they were both 18 months old and bought 3 weeks apart, so I put it down to hipers just being rubbish more than the pc being too powerful

As for SLI 7800's I would def make sure you have the latest chipset drivers for your mobo coz if you look in my sig you'll see im v.similar spec and my 7800s are udnerperformaing looking at my 3dmark05 score, I put it down to the fact I'm still running the original chipset drivers I got with my mobo, but I cba to update since I'm getting rid of it and going C2D v.soon

Although I will be keeping the 7800s in my new rig til a decent dx10 card comes out...cba with 8800, they will be the lowest of the low dx10 cards soon enough so no point concidering there are no/very few dx10 games at the moment

 

[pastymuncher]

i was running SLI 7800's in my hiper 580...it blew up
but then again my m8 had the same psu but was only running a 6600gt and it did exactly the same as mine...3 weeks apart, they were both 18 months old and bought 3 weeks apart, so I put it down to hipers just being rubbish more than the pc being too powerful

As for SLI 7800's I would def make sure you have the latest chipset drivers for your mobo coz if you look in my sig you'll see im v.similar spec and my 7800s are udnerperformaing looking at my 3dmark05 score, I put it down to the fact I'm still running the original chipset drivers I got with my mobo, but I cba to update since I'm getting rid of it and going C2D v.soon

Although I will be keeping the 7800s in my new rig til a decent dx10 card comes out...cba with 8800, they will be the lowest of the low dx10 cards soon enough so no point concidering there are no/very few dx10 games at the moment

Are you running the 93.71 drivers by any chance? I could'nt run that set with my 7800's as they took a large performance hit with them. Try 91.47, it should make a big difference. It did with mine anyway. I had an Abit AN8-32X sli, 2gb pc3200 and a pair of BFG 7800gt OC's.

 

[chaparral]

Hipers are not capable of outputting their claimed 580w either.

The combined maximum wattage for the 12V rail is only 360watts...http://www.jonnyguru.com/review_details.php?id=26

 

[bluntslide]

just got my 7800gtx sli up and running, 93.81 drivers are working best at the minute (8905 3dmark06). found myself enabling sli via the advanced display properties and stumble across that gpu load bar? switched it on just to prove in my head that sli was working but after the first run of 06 it was already clear, test 1 showed 50+ fps, that was good enough for me!
my sphincter is twitching a bit now people are posting about the hiper. im running a 580 type r........

 

[MuSsEr]

what do you get in 3dmark05?

 

[LSPIII]

what do you get in 3dmark05?

Not sure you were asking me but meh

I've done some tests on my setup pre-SLI so I can tell the difference when the SLI is put in place.

3D Mark '05 Stock: 7792
3D Mark '05 Overclocked GPU: 8830
3D Mark '06 Stock: 4318
3D Mark '06 Overclocked GPU: 4795

Not sure if those scores are actually any good for my type of setup but that's what they are anyway!

I'll let you know what I get when the second card arrives. Hopefully today

 

[pastymuncher]

05 sounds about right. My 7800gt's heavily clocked would get 7747.
06 seems low though, especially as it's multi core threaded. What's your cpu clocked at?

I got 6315 with a 754 3700+ @2.795ghz and the two 7800gt's @500/1.20.

 

[LSPIII]

06 seems low though, especially as it's multi core threaded. What's your cpu clocked at?

Stock! Never really tried OCing the 4400X2 to be honest. I'm also in the process of making my machine as silent as possible, hence the lack of overclocking. I'll run the graphics cards at stock speed as well, just to prevent excess heat building up in the case. I do only have one graphics card in there at the moment and it may have something to do with XP x64 perhaps?

 

[LSPIII]

3D Mark '05 Stock: 7792
3D Mark '05 Overclocked GPU: 8830
3D Mark '06 Stock: 4318
3D Mark '06 Overclocked GPU: 4795

I'll let you know what I get when the second card arrives. Hopefully today

So the second 7800GTX is installed and running now. I have run 3D Mark again to some, well... bizarre scores:
3D Mark '05 Stock SLI: 11328
3D Mark '05 Overclocked GPU SLI: 11242
3D Mark '06 Stock SLI: 6776
3D Mark '06 Overclocked GPU SLI: Was heading the same way as '05 overclocked, only I noticed a frame rate drop qhwn compared with stock this time, so just aborted the test.

I'm relatively happy about the stock result. I should be able to run FEAR at 1920x1200 now with everything on (was so close to having it run nicely before SLI), as well as Test Drive Unlimited, so that makes me happy.

What do you guys make of the scores?

 

[MuSsEr]

must be my chipset drivers that i cant be arsed to update

look at my 05 score in my sig, 3dmark05: 10253 3dmark06: 5460

with two 490/1300 7800's

06 seems fine for my cpu being only single core and a 3500+ but my 05 seems well low compared

Hopefully it'll improve vastly when I get my new mobo and cpu and ram and actually bother formattign with latest chipset drivers, lol

 

[spb251272]

I should be able to run FEAR at 1920x1200 now with everything on (was so close to having it run nicely before SLI), as well as Test Drive Unlimited, so that makes me happy.

I wouldn't be so sure - I was running FEAR XP last night at 1680 x 1050 with every maxed (including SS Transparency AA set), and my ave. fps was 58. This is with a [email protected] and an 8800GTX @ 648/2042, and my 3D Mark 06 score is 12258.

 

[bluntslide]

I think you will see a jump after the upgrade, I reckon I could break 9k if I could be arsed but its plenty for now!

 

[james.miller]

So the second 7800GTX is installed and running now. I have run 3D Mark again to some, well... bizarre scores:
3D Mark '05 Stock SLI: 11328
3D Mark '05 Overclocked GPU SLI: 11242
3D Mark '06 Stock SLI: 6776
3D Mark '06 Overclocked GPU SLI: Was heading the same way as '05 overclocked, only I noticed a frame rate drop qhwn compared with stock this time, so just aborted the test.

I'm relatively happy about the stock result. I should be able to run FEAR at 1920x1200 now with everything on (was so close to having it run nicely before SLI), as well as Test Drive Unlimited, so that makes me happy.

What do you guys make of the scores?

holy moly i dont want to be captain predictable response, but you'd be better of selling both cards and getting an 8800gts/gtx. my stock score is a good 4k higher in '06 and 6k higher in '05

 

[LSPIII]

holy moly i dont want to be captain predictable response, but you'd be better of selling both cards and getting an 8800gts/gtx. my stock score is a good 4k higher in '06 and 6k higher in '05

I got the second card for cheap, who was I to say no! The 7800s don't go for much any more on the second hand market, so if I was to sell them both I would still need to put more cash in to get an 8800GTS let alone a GTX! I just don't have the money for that right now. Having the second card has made a real difference though. Fear is playable with everything on full at 1920x1200, I get the occasional jerking, but not a lot fortunately, so I can live with it.

 

[Perfect_Chaos]

do 2 cards in SLI always get outpaced by a single card a year later?

 

[LSPIII]

do 2 cards in SLI always get outpaced by a single card a year later?

Not sure about a year later, maybe close to 18 months. My two 7800GTXs will outpace a 7900GTX single setup, and that was the card that replaced mine originally. The 8800 series cards really are just a massive step up though, unusually so I'd have said. That said though, Moore's Law states a doubling of power every two years so I guess about 18 months is about right.