7770HD Crossfire

[jayantfordreams]

Hey Guys This is Jayant..from india,
I'm going to crossfire 7770HD, can i do it with a 450w PSU ??
Also check my specs and power usage on partpicker:

http://pcpartpicker.com/user/cse.jayant/saved/1QRC

My system config:
i3 3220, 7770HD 1GB Sapphire GHz edition, 4GB Kingston HyperX Blu 1600Mhz, 500GB WD 7200RPM, ASUS DVD-RW Sata 24x,AOC 2260 22" and PSU: 450w Cooler master Thunder 450 --> http://www.flipkart.com/cooler-master-thunder-450w-450-watts-psu/p/itmdbm7fpuzpszvf

Here's the deal, my overall system power usage is around 225 watt at full load let's just say for crossfire i need extra 80-85 watts, considering 80-85% of efficiency of PSU it should work..theoretically.

I want to know if there are major geeks around this site Pls. Help whether it would work or just blowing up PSU itself.

Secondly, i had an extra local 2004 make PSU 220watts from my older Junk PC i can use it alone to supply power to the 2nd GPU for crossfire. using molex to 6 pin connector will it work ??

What option would be better One 450Watt PSU or Two 450Watt+220Watt PSU.

 

[Mr Expert]

That PSU will run your rig with no issues.

 

[Face2Face]

It may run fine since the 7770's don't draw much (180watts?). I am trying to figure out the North American comparable model for the PSU. I think's its the eXtreme 500w? If so, keep this in mind below..

This is from a CM reps mouth -

"Yeah, the eXtreme Power 500W really just sucks. They can last a while if you don't overload them, because there isn't much in there that can go wrong. But performance is bad and they can't actually do 500W"

I actually have one and it did fine with an AMD Triple-core @ 3.1Ghz and a GTX 260 - I still have it and still works with no issues. I assume you would be fine... if it starts buzzing under load then don't use it I hooked mine up to a 8320 and GTX 560ti 448 and yeah... it didn't like running Heaven...

 

[frozentundra123456]

Is it possible to sell the 7770 that you have and buy a 2gb 7850 or 7870? It is generally better to run one single card of higher performance rather than two low/mid range cards, especially since the 7770 cards have only 1gb of video memory.

 

[3DVagabond]

That PSU is fine. It's made by Enhance which is a decent OEM. The eXtreme 500w is made by Seventeam who aren't as good overall, IMO.

 

[jayantfordreams]

Is it possible to sell the 7770 that you have and buy a 2gb 7850 or 7870? It is generally better to run one single card of higher performance rather than two low/mid range cards, especially since the 7770 cards have only 1gb of video memory.

That would be a decent option but In my country no one will buy it in even half the cost..that's why i'm up to crossfire. 7770HD crossfire==2GB 7870 anyways.

 

[boxleitnerb]

7770HD crossfire==2GB 7870 anyways.

No. Profile dependency, microstuttering and only 1 GB memory (memory doesn't double with CF/SLI, it's redundant). Even with AMDs new frame pacing drivers, CF with a low-end card makes no sens in my opinion.

 

[spat55]

It'll easily run it, the only thing is most Cooler Master PSU's are rather weak, still it will run fine, and if you had a seasonic you could get away with 350-400w

 

[Yuriman]

That would be a decent option but In my country no one will buy it in even half the cost..that's why i'm up to crossfire. 7770HD crossfire==2GB 7870 anyways.

Memory is not doubled with Crossfire. Chances are it will perform similarly to an HD7850 1GB in most games, but be aware that Crossfire only works in fullscreen and on occasion doesn't scale at all, leaving you with the performance of a single HD7770.

 

[spat55]

Memory is not doubled with Crossfire. Chances are it will perform similarly to an HD7850 1GB in most games, but be aware that Crossfire only works in fullscreen and on occasion doesn't scale at all, leaving you with the performance of a single HD7770.

Think he would be better off selling it then getting a HD 7850, the amount they cost now would only cost him an extra few quid.

 

[Yuriman]

Think he would be better off selling it then getting a HD 7850, the amount they cost now would only cost him an extra few quid.

Tough to say.

For me, Crossfire is what you do when you end up with two cards as hand-me-downs to extend the life of old hardware, or if you want to run Eyefinity on top end hardware, and makes little sense otherwise. That said, I put an identical HD7850 in my wife's PC so I can Crossfire them down the road when I eventually upgrade. It's difficult for me to rationalize buying a second card unless there are special circumstances - such as the poor re-sale market in his country.

EDIT:

For a short while I did run my rig on 3x 250w PSUs when my good PSU crapped out, so I know personally that it can work. The wiring was an unsightly mess though. I bet you'll be fine with your 450w but you do have the option.

 

[Schmide]

The 7770 is a 100w card.

The PSU is rated at 360w.

OP is pulling 225w (load wall) or 170w (system). So he's running at about 50% of the PSUs rated load. You really don't want to go above 75% of the rated amount. Especially on a aged PSU. So if you add a 100w card into the mix, you're looking at 270w, which is exactly 75% of 360w. Yay

The one thing the OP has going for him is the i3 3220 is a very efficient CPU. Prob pulling 40-50w cpu without graphics (60-70w with graphics active).

Most ratings for cards and CPUs are made for the greatest common denominator. With higher end CPUs entering the 125-140w level, peripherals sucking up to 50w, and companies rating their CPUs way higher than they actually perform, it's no wonder 500-600w PSUs are recommended for crossfire.

So I think it will work, if the psu is dust free and you organize your power so your HD, fans, DVD is on one lead and the graphics card is on the other.

 

[Schmide]

I'm sure there are some runt frames in these benches.

http://www.tweaktown.com/reviews/4572/sapphire_radeon_hd_7770_1gb_oc_video_cards_in_crossfire/index.html

You're looking at 7950 performance. So minus the runts 7870 easy.

Edit: Notice their system pulls 379w (wall) with an I7-3960 EE @ 4.7ghz (ssd only). You could easily make the case that that system (i.e. the cpu) is 100w more than yours.

 

[Yuriman]

I'm sure there are some runt frames in these benches.

http://www.tweaktown.com/reviews/4572/sapphire_radeon_hd_7770_1gb_oc_video_cards_in_crossfire/index.html

You're looking at 7950 performance. So minus the runts 7870 easy.

Edit: Notice their system pulls 379w (wall) with an I7-3960 EE @ 4.7ghz (ssd only). You could easily make the case that that system (i.e. the cpu) is 100w more than yours.

Very surprising, as an HD7770 is exactly half of an HD7870. HD7950 has 40% more shaders and 66% more memory bandwidth than two 7770's, in addition to being clocked higher. Does increasing shaders scale better via crossfire than by increasing the amount on a single die with the 7000 series?

 

[boxleitnerb]

The 7950 is more than twice as fast as the 7770. 7770 CF cannot be as fast or faster than the 7950. The OP has the normal version, not the OC.

 

[Leyawiin]

TechPowerUP has a review of HD 7770 CF. Power consumption was about like a single GTX 460 1GB at maximum (and about 13w less in average gaming).

 

[frozentundra123456]

Very surprising, as an HD7770 is exactly half of an HD7870. HD7950 has 40% more shaders and 66% more memory bandwidth than two 7770's, in addition to being clocked higher. Does increasing shaders scale better via crossfire than by increasing the amount on a single die with the 7000 series?

Those results are indeed very surprising (questionable??).

They are getting perfect scaling with crossfire. Seems too good to be true to me.

 

[Durvelle27]

I would rather have a single HD 7870 or HD 7950 than two lower end cards with only 1GB of VRAM.

 

[Leyawiin]

I have an ASUS HD 7770 2GB in a secondary rig (got it for a about $100 after MIR). I might consider getting another given it has 2GB VRAM. Erm... maybe... probably not.

 

[jayantfordreams]

Thanks Guys !! for all the Replies... i might not require another P.S.U only the time will say how much long it lasts.