4890 Crossfire time

[Dravic]

I have a quality Power supply PC Power & Cooling S61EPS 610W, but I'm thinking It might be a bit close for 4890's crossfired.

80% efficiency puts me at 480+ watts which seems to be enough, and 4890's x 2 shouldn't exceed 400 watts for average use.

The 4890's @ $169 are looking pretty tempting right about now.

Bah....

 

[v8envy]

You got that backwards. 610 watts is what your PSU is rated for on the DC side. Which means it'll draw about 760 watts from the wall. So long as you're not in a hot environment and your PSU is relatively new you should be good for 2x 5850s even with your OCd CPU as long as you don't have too many hard drives or case fans.

 

[error8]

That PSU has 49 Amps on the 12 V rail, which means you have 588 Watts to play with.
2x4890 will suck 190X2 W + 150 W with your heavily oced cpu will take you to 530 W. Now, if we add the rest of the components, we get pretty close to 588 W. It will probably hold your cross fire, but it will be a bit close to the limit. A 750 W Corsair PSU is a safer bet.

 

[happy medium]

Heres a review of 4890's crossfired. With a overclocked core i7 (@3.8), and a Raptor hard drive total watts under load was 420watts.

I think you'll be fine.

http://www.techpowerup.com/rev...4890_CrossFire/23.html

http://www.xbitlabs.com/articl...-hd4890cf_7.html#sect0

 

[Schmide]

Originally posted by: error8
That PSU has 49 Amps on the 12 V rail, which means you have 588 Watts to play with.
2x4890 will suck 190X2 W + 150 W with your heavily oced cpu will take you to 530 W. Now, if we add the rest of the components, we get pretty close to 588 W. It will probably hold your cross fire, but it will be a bit close to the limit. A 750 W Corsair PSU is a safer bet.

What what what what (South Park Kyle's mom's voice). Even on ATI's marketing papers the wattage of a 4890 is a 150w envelope card, reality putting them in the 130w envelope. If you're pushing the sale of a Corsair PSU you're doing a good job. Doing all the math for his computer, I see no way his power footprint will get over 450w on the 12v.

 

[edplayer]

I agree with Schmide

 

[toyota]

Originally posted by: Schmide

Originally posted by: error8
That PSU has 49 Amps on the 12 V rail, which means you have 588 Watts to play with.
2x4890 will suck 190X2 W + 150 W with your heavily oced cpu will take you to 530 W. Now, if we add the rest of the components, we get pretty close to 588 W. It will probably hold your cross fire, but it will be a bit close to the limit. A 750 W Corsair PSU is a safer bet.

What what what what (South Park Kyle's mom's voice). Even on ATI's marketing papers the wattage of a 4890 is a 150w envelope card, reality putting them in the 130w envelope. If you're pushing the sale of a Corsair PSU you're doing a good job. Doing all the math for his computer, I see no way his power footprint will get over 450w on the 12v.

ATI lists the 4890 as being 190watt TDP and it said that on all its slides at release. now of course it doesnt get any where near that in reality so I agree he should be just fine.

he will likely hit about 500 watts at the wall according to this review: http://www.tweaktown.com/artic...crossfire/index11.html but only about 420 watts according to this one: http://www.techpowerup.com/rev...4890_CrossFire/23.html

 

[Schmide]

Originally posted by: toyota
ATI lists the 4890 as being 190watt TDP and it said that on all its slides at release. now of course it doesnt get any where near that in reality so I agree he should be just fine.

he will likely hit about 500 watts at the wall according to this review: http://www.tweaktown.com/artic...crossfire/index11.html but only about 420 watts according to this one: http://www.techpowerup.com/rev...4890_CrossFire/23.html

TDP = thermal design power != actual usage.

As for the two articles that's at the wall which is not equal to actual usage. (20% off 500w=400w)

 

[toyota]

Originally posted by: Schmide

Originally posted by: toyota
ATI lists the 4890 as being 190watt TDP and it said that on all its slides at release. now of course it doesnt get any where near that in reality so I agree he should be just fine.

he will likely hit about 500 watts at the wall according to this review: http://www.tweaktown.com/artic...crossfire/index11.html but only about 420 watts according to this one: http://www.techpowerup.com/rev...4890_CrossFire/23.html

TDP = thermal design power != actual usage.

As for the two articles that's at the wall which is not equal to actual usage. (20% off 500w=400w)

I know TDP is not actual usage. I was saying the only official numbers that I saw ATI lists. last time I looked both companies listed TDP not actual power usage. if anything ATI actually does get much closer to TDP than Nvidia does. in other words Nvidias TDP is usually WAY higher than actual power consumption. plus power consumption and TDP are related a lot more than you think or they wouldnt put a power connector on a card that was just borderline with its TDP.

I also know that at that wall is not actual power usage thats why I clearly said "at the wall" in the first place. if you read my comment I am agreeing with you and saying he will be just fine.

 

[Schmide]

Originally posted by: toyota
I know TDP is not actual usage. I was saying the only official numbers that I saw ATI lists. last time I looked both companies listed TDP not actual power usage. if anything ATI actually does get much closer to TDP than Nvidia does. in other words Nvidias TDP is usually WAY higher than actual power consumption. plus they are related a lot more than you think or they wouldnt put a power connector on a card that was just borderline with its TDP.

I also know that at that wall is not actual power usage thats why I clearly said "at the wall" in the first place. if you read my comment I am agreeing with you and saying he will be just fine.

I wasn't disagreeing. I was adding information so people wouldn't draw a different conclusion. If you quote an at the wall figure you should do the math to make the distinction relative to internal usage.

 

[error8]

Originally posted by: Schmide

Originally posted by: error8
That PSU has 49 Amps on the 12 V rail, which means you have 588 Watts to play with.
2x4890 will suck 190X2 W + 150 W with your heavily oced cpu will take you to 530 W. Now, if we add the rest of the components, we get pretty close to 588 W. It will probably hold your cross fire, but it will be a bit close to the limit. A 750 W Corsair PSU is a safer bet.

What what what what (South Park Kyle's mom's voice). Even on ATI's marketing papers the wattage of a 4890 is a 150w envelope card, reality putting them in the 130w envelope. If you're pushing the sale of a Corsair PSU you're doing a good job. Doing all the math for his computer, I see no way his power footprint will get over 450w on the 12v.

Now all this discussion has been made some time ago, (you seem to have missed it) and all the electrical power that a videocard sucks it will be transformed entirely into heat, so by using this, we can conclude that TDP is the actual power consumption of the card. It's Physics you know, nothing new.
Now a 4890 will probably never touch the 190 W power consumption, in normal use in games, but only by forcing it with programs like Furmark. But then again, maybe the OP will use Furmark sometime, to test for stability or just because he wants to. So, I really don't see my recommendation out of the line here, since even on GURU 3d review they do recommend for a high end system at the very least a 750-800 Watts PSU. A high end system is something that OP has, where his Phenom quad core chips is overclocked to hell and back.

 

[Schmide]

Originally posted by: error8
Now all this discussion has been made some time ago, (you seem to have missed it) and all the electrical power that a videocard sucks it will be transformed entirely into heat, so by using this, we can conclude that TDP is the actual power consumption of the card. It's Physics you know, nothing new.
Now a 4890 will probably never touch the 190 W power consumption, in normal use in games, but only by forcing it with programs like Furmark. But then again, maybe the OP will use Furmark sometime, to test for stability or just because he wants to. So, I really don't see my recommendation out of the line here, since even on GURU 3d review they do recommend for a high end system at the very least a 750-800 Watts PSU. A high end system is something that OP has, where his Phenom quad core chips is overclocked to hell and back.

I understand the conservation of energy. What you seemed to have missed is the design in thermal design power.

As for the Fur mark, it will never reach 190w either. The digital voltage regulators will cause it to throttle not the actual chip. A card without them will not throttle.

I would also take the guru3d's results as a bit off, an overclocked i7 with its dual power planes and hungry chipset is probably eating a lot of that power. (on the 12v 225w = 175w i7 chip and uncore + 50w chipset)

In the end, it just seemed a bit viral marketing for you to recommend a brand and wattage PSU for the task with what I saw as inflated figures.

 

[error8]

Originally posted by: Schmide


I understand the conservation of energy. What you seemed to have missed is the design in thermal design power.

As for the Fur mark, it will never reach 190w either. The digital voltage regulators will cause it to throttle not the actual chip. A card without them will not throttle.

I would also take the guru3d's results as a bit off, an overclocked i7 with its dual power planes and hungry chipset is probably eating a lot of that power. (on the 12v 225w = 175w i7 chip and uncore + 50w chipset)

In the end, it just seemed a bit viral marketing for you to recommend a brand and wattage PSU for the task with what I saw as inflated figures.

I was just putting out a quality 750 W PSU, at a fair price, for the OP as an option, if he decides to get a new PSU. Please, spare me with the fanboysm concept since I have nothing to do with Corsair or other brands. If I was to work for Corsair I would have used one of their PSUs and put it in my sig.

This article here puts 4870 under load at almost 200 watts with Furmark, so your assumptions about throttle are wrong.

 

[Dravic]

Originally posted by: v8envy
You got that backwards. 610 watts is what your PSU is rated for on the DC side. Which means it'll draw about 760 watts from the wall. So long as you're not in a hot environment and your PSU is relatively new you should be good for 2x 5850s even with your OCd CPU as long as you don't have too many hard drives or case fans.

Ty for that, i always thought it was the other way...



I'll prob give it a shot and if i experience stability/power issues pick up a 750-800W PSU.


I've actually back down the CPU a bit once i found the max, at 1.41v @ 3.5 currently..

 

[Dravic]

It's alive..... ITS ALIVE...

Just an FYI.. been up and running with the current power supply for about a month.

From the UPS:
Both cards installed

Crossfire disabled in 3dmark06 = ~360watts
Crossfire enabled in 3dmark06 = ~450watts

like butter...




The suprising part was:

2 computers ( 1 in sig)

2nd:
2 opteron 275 (4 cores total)
Tyan workstation board
2 hard drive ~750GB
dvd burner
7800gt


all pull less then 600W from the wall with monitors (crossfire disabled.. was playing WOW).

 

[M1A]

Crossfire question to OP or for that matter anyone that knows....., Could you have a crossfire setup with Win 7 and a 4890 and a 4870 and if you can would it be much faster than just the 4890. I ask because a I have a 4870 coming back from an RMA and I bought a 4890 till it came back.

 

[happy medium]

Crossfire question to OP or for that matter anyone that knows....., Could you have a crossfire setup with Win 7 and a 4890 and a 4870 and if you can would it be much faster than just the 4890. I ask because a I have a 4870 coming back from an RMA and I bought a 4890 till it came back.

It will work fine. You should try to overclock the 4870 to 4890 speeds if possible.

It will be as fast as a 2 4870 in crossfire.

Edit: I hope your 4870 is a 1gb card, not 512mb?

 

[Udgnim]

links to 4890 Crossfire power consumption:

http://www.tweaktown.com/articles/2704/ati_radeon_hd_4890_in_crossfire/index11.html
http://www.techpowerup.com/reviews/ATI/HD_4890_CrossFire/23.html

please note the reviewer's load method and system setup

 

[M1A]

To reply above yes its a 1G 4870. I will give it a shot........

 

[M1A]

Dravic, I see you are using the Soyo 24" aren't they great!!!!!!!!!For the price they could not be beat 2 years ago. I still use mine 24/7. I tried to go to a 32 Sony XBR and returned it. I guess the Soyo spoiled me. Sorry OP I know this is off topic.