WEIGH IN: $1200 AMD system for Sept. SBM

[cleeve]

[EDIT]

This poll is no longer valid - after a lot of playing around, I think we'll be going with the following system: a Phenom II X4 945 with four Radeon HD 4850's in quad-CrossFire:

http://secure.newegg.com/WishList/PublicWishDetail.aspx?WishListNumber=11540352



It seems like the right thing to do...

 

[hunter315]

We know what a 955 and 2 4890s can do, i would assume the 945 to be nearly identical, i would love to see what an OC'ed 720 and 4870x2s can do.

Any chance of getting a review that compares the hit from 8x/8x vs 16x/8x vs 16x/16x crossfire for a variety of cards if the 720 system does show up with a large bottleneck?

btw you posted the link to the 720 one for both.

 

[dirtmountain]

I'm getting the same build off the wishlist.

 

[DavidTJ]

If this system builder marathon is purely on gaming and you can use all those cards to the full extent then the budget gamer build might cause an upset.

So my vote goes for the budget gamer build, if it was all round performance I'd go for the more balanced build.

 

[Outlander_04]

In the article about 2 , 3 or 4 cores there are gaming situations in intense games that show cpu limitations

http://www.tomshardware.com/reviews/amd-cpu-overclock,2304-7.html

"Sure enough, the results indicate a CPU limitation and not a GPU limitation. The narrower the aspect ratio, the higher the performance, yet the number of pixels pushed had no effect on performance. Keep in mind that there are a lot of physics effects going on this Crysis bench, so this is not a blanket statement to apply toward all games. In fact, even the reverse could hold true in other titles. However, this also isn’t the first game in which we have seen CPU-limited settings that resulted in lower performance at wider aspect ratios. "

This suggests the 720 will pay off in some games by not affecting fps much, but its not going to cut it in environments with high particle counts and so on .
All the systems in that article used a single 4870, and I suspect crossfiring two cards will make the cpu's job even harder .
That suggests [ to me anyway ] that its not worth it to run with the 720 for this build

I dont think I have ever been more vague about anything LOL

 

[Outlander_04]

well ,not since I gave up drinking

 

[dirtmountain]

I'm not sure about a 700w power supply for 2x 4870X2s, you're looking at 500+ watts just for the graphic cards.

 

[freezed1]

lol Daring move..but it will certainly answer some questions. Gl

 

[Shadow703793]

@OP: The title says "$1200 AMD" but this:
http://secure.newegg.com/WishList/PublicWishDetail.aspx?WishListNumber=11540352
is $1300 that's a $100 difference! AND you linked the same one twice.

 

[Helloworld_98]

the 945 + 4890's, because that 700w PSU isn't going to take 2x 300w cards, a 95w CPU (which will probably end up being more like 120w when you're done oc'ing) and some more gubbins.

 

[dirtmountain]

Although the "official" budget may be pegged at $1,200, SBM builds often go a bit over budget just like regular buyers will go a bit over budget if they think the price/performance is worth it. The last SBM article had the middle build at $1,300. Cleeve may be able to do a compromise with 3- 4870 1GB in tri crossfire, the PhenomII 945 with the MSI 790FX motherboard and the build i posted on the other thread and still come very close to the $1,200 proposed budget. Or a 780i , DDR2, tri SLI with GTX260s could work also.

 

[nerrawg]

I have a feeling that 2x 4870X2 cards will be the same as last time you guys tried, as in that they hardly scale better than a single 4870 X2.

dual 4870X2:
http://www.tomshardware.com/reviews/system-builder-marathon,2056-3.html
single 4870X2:
http://www.tomshardware.com/reviews/cpu-graphics-overclocking,2083-12.html

also (sorry to mention this) anandtech also did a very comprehensive GPU scaling 4-part article in which the quad-fire 4870 didn't add that much in some situations:

however it did do better in crysis in this test than in your own system builder. (probably I7 and graphics settings)

What I think would be really interesting to see would be 2 x 4890's overclocked as far you could push them versus 2 x 4870X2's OC'ed.
I might be wrong (and I would love to find out), but I reckon the 4890's in CF will almost match the 4x 4870's in games like crysis and far cry 2?

I think the best compromise between ultimate performance and scaling percentage would be tri-fire 4890's.
In fact if you could get 3 x 4890's and a X3 720 or even possible if you had to an X2 550 BE I think you would be on to a winner (at least in gaming fps) regardless of the lack of CPU power.

Tri-fire 4890's would be great as well because hardly anyone has benches on this kind of configuration, the limits of overclocking and power draw.
However I would understand if this is not within the financial restraints as it requires an expensive 790FX board in addition to 3x 4890's.

I have a weird hypothesis, which I don't know if it really is scientifically sound, but it seems to me that the RV700's don't really start to unleash good scaling in tri and quad fire until their core speeds get above 800 mhz - the only reason being that slower core clocks like on the 4850 don't scale near as well in tri and quad fire as the 4870, and the same can be said for the 4870 vs the 4890 in tri-fire. However never seen any quad-fire 4890 results - don't know if it is doable even though there are 790FX boards with 4 PCI lanes dually spaced.

Anyways I will be looking forward to the next builder's marathon - best of luck Cleeve!

 

[cleeve]

I'm getting the same build off the wishlist.

doh! Fixed

 

[cleeve]

is $1300 that's a $100 difference! [/b]

I know. It's more of a guideline than a rule though, and the X3/2x 4870 X2 system wasn't do-able without it. The regular Phenom II 945/2x 4890 system fits under $1200 pretty easily though.

 

[Shadow703793]

@nerrawg: +1. Agreed.

 

[Outlander_04]

when you do bench this thing can you also give results for 2 and 3 gfx cards as well ?

 

[dirtmountain]

Hmmm only 21.8 fps less then tri 260s and 21.2 fps less then tri 4870 1GB....... uhh the way to go ?