Latest Thread Images

PC Enthusiast-Fi (PC Gaming/Hardware/Software/Overclocking)
Nov 23, 2013 at 9:31 PM Post #3,436 of 9,120
deadlylover said:
   
Pay the $6 you cheap person. 
tongue.gif

 
I'd help, but I'm on the other side of the world.
Click to expand...

And that's why I'm still here.
 
I'm a cheap person and would rather some guy with an unused bridge tell me otherwise.
 
I have all week to wait anyway
 
Nov 24, 2013 at 1:26 AM Post #3,439 of 9,120
Anyway, new post of mine. Help me out please.
 
I know what information to provide to you guys and have a good understanding of power and rails and stuff like that in terms of how they work and in generally what is safe. I'm unsure about some things so I'll be providing all the information needed. 
 
I just need help on if my PSU has the power in its rails and on the safety of using periph adapters for pcie connectors
 
Thanks guys
 
I am thinking of getting two AMD 7870 GHz Editions

I currently have this PSU
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341018

 Is the Rails on the back of it

I have read the review for the CF 7870 and have noted the power consumption stated in that systems test as well as the AMD home page seen here:
http://www.amd.com/US/PRODUCTS/DESKTOP/GRAPHICS/7000/7870/Pages/radeon-7870.aspx#3
http://www.tweaktown.com/articles/4597/amd_radeon_hd_7870_2gb_reference_video_cards_in_crossfire/index16.html
http://www.tweaktown.com/articles/4597/amd_radeon_hd_7870_2gb_reference_video_cards_in_crossfire/index2.html

Notice that the 500W load is the total from the entire test setup from the two linked articles. It was stated that it was running on bare minimums but that is still a somewhat hefty test setup.

I also note that the 7870 requires two six pin power connectors. My PSU only has two and I need for. I am not using most of the extra peripheral connectors on my PSU.

I know most if not all the information I need to provide to you guys. I just don't know how to interpret the amps and rails on the PSU and on the safety of using an adapter that changes periph connect to 6pin connector.

So yeah, is using an adapter for the second cards power connectors safe and does my PSU have enough power on its rails for both the cards?

My computer will be changed and re-updated for this setup and will feature
AMD Phenom II X4 965 Be (Stock Clock)
Corsair H50 Liquid AIO (two 12cm fans)
128GB SSD
Two physical hard drives (non green drives)
One or Two 12cm case fans (no led)
Disk Drive

I used to use an APC UPS with power monitor with my computer and I got an estimate of my computer (with much more fans w/ leds and more HDD's) of 150W idle and 220W Load. This was with my old 5770 as well. Just for more information for you power crunching guru's.
 
Nov 24, 2013 at 1:34 AM Post #3,440 of 9,120
http://www.tomshardware.com/forum/329264-28-good-crossfire
http://hardforum.com/showthread.php?t=1730623
 
First guy notes 39A on 12V rails. 
 
My PSU is multi rail(I read the OCN article on it) and so is the 25V on each rail then combined for 50V? If so I should be fine.
 
If that is true, then last question would be on using my molex to 6 pin or 8pin to 6 pin adapters and if there will be any problems with that.
 
Nov 24, 2013 at 6:21 AM Post #3,441 of 9,120
bowei006 said:
  If that is true, then last question would be on using my molex to 6 pin or 8pin to 6 pin adapters and if there will be any problems with that.
Click to expand...

 
Pay attention to the rails for when you're plugging the cards in, the PCI express and the molex peripherals (for your 4 pin to 6 pin adapters) should be on different rails, just make sure that they are. If your power supply is modular, it might tell you what connectors are using which of the two 12V rails.
 
The TDP's for the 7870's are about 175W, two of them will run 350W and your CPU has a TDP of 140W, it might be cutting it a bit close, but I doubt you'll be able to draw that much power in normal heavy gaming use, and even if you're doing some crazy power heavy stress tests, I think you're juuuuust within the limit. I'd like to re-emphasise, those are worst case scenarios, you'd have to be deliberately go out of your way to draw as much power as you can by using cherry-picked stress tests and what not.
 
I'd worry about it when it becomes a problem. 
tongue.gif
 
 
Nov 24, 2013 at 9:21 AM Post #3,442 of 9,120
deadlylover said:
Pay attention to the rails for when you're plugging the cards in, the PCI express and the molex peripherals (for your 4 pin to 6 pin adapters) should be on different rails, just make sure that they are. If your power supply is modular, it might tell you what connectors are using which of the two 12V rails.

The TDP's for the 7870's are about 175W, two of them will run 350W and your CPU has a TDP of 140W, it might be cutting it a bit close, but I doubt you'll be able to draw that much power in normal heavy gaming use, and even if you're doing some crazy power heavy stress tests, I think you're juuuuust within the limit. I'd like to re-emphasise, those are worst case scenarios, you'd have to be deliberately go out of your way to draw as much power as you can by using cherry-picked stress tests and what not.

I'd worry about it when it becomes a problem. :p  
Click to expand...


Be careful. TDP is not necessarily the same as power consumption. It should equal power consumption under full load but typically is off. Try using extreme power supply calculator. It will give a reasonable estimate of your power usage.
 
Nov 24, 2013 at 10:15 AM Post #3,443 of 9,120
bowei006 said:
  Anyway, new post of mine. Help me out please.
 
I know what information to provide to you guys and have a good understanding of power and rails and stuff like that in terms of how they work and in generally what is safe. I'm unsure about some things so I'll be providing all the information needed. 
 
I just need help on if my PSU has the power in its rails and on the safety of using periph adapters for pcie connectors
 
Thanks guys
 
I am thinking of getting two AMD 7870 GHz Editions

I currently have this PSU
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341018

 Is the Rails on the back of it

I have read the review for the CF 7870 and have noted the power consumption stated in that systems test as well as the AMD home page seen here:
http://www.amd.com/US/PRODUCTS/DESKTOP/GRAPHICS/7000/7870/Pages/radeon-7870.aspx#3
http://www.tweaktown.com/articles/4597/amd_radeon_hd_7870_2gb_reference_video_cards_in_crossfire/index16.html
http://www.tweaktown.com/articles/4597/amd_radeon_hd_7870_2gb_reference_video_cards_in_crossfire/index2.html

Notice that the 500W load is the total from the entire test setup from the two linked articles. It was stated that it was running on bare minimums but that is still a somewhat hefty test setup.

I also note that the 7870 requires two six pin power connectors. My PSU only has two and I need for. I am not using most of the extra peripheral connectors on my PSU.

I know most if not all the information I need to provide to you guys. I just don't know how to interpret the amps and rails on the PSU and on the safety of using an adapter that changes periph connect to 6pin connector.

So yeah, is using an adapter for the second cards power connectors safe and does my PSU have enough power on its rails for both the cards?

My computer will be changed and re-updated for this setup and will feature
AMD Phenom II X4 965 Be (Stock Clock)
Corsair H50 Liquid AIO (two 12cm fans)
128GB SSD
Two physical hard drives (non green drives)
One or Two 12cm case fans (no led)
Disk Drive

I used to use an APC UPS with power monitor with my computer and I got an estimate of my computer (with much more fans w/ leds and more HDD's) of 150W idle and 220W Load. This was with my old 5770 as well. Just for more information for you power crunching guru's.
Click to expand...

This schiit is why I buy single rail PSUs

 
Though, Deadly is right, high load on the bigger rail, low load on the smaller one.
 
Nov 24, 2013 at 12:30 PM Post #3,444 of 9,120
tangster said:
  This schiit is why I buy single rail PSUs

 
Though, Deadly is right, high load on the bigger rail, low load on the smaller one.
Click to expand...

LOL
 
 
Run furmark/prime95 and make sure that the PSU isn't being strained...
I don't know OCZ's reputation when it comes to PSUs, but shouldn't be anything like Diablotek haha.
 
Should hear some whines and buzzing if you're skating on thin ice.
 
My PSU is about to turn 7 in a few months lol.
 
Nov 24, 2013 at 2:37 PM Post #3,447 of 9,120
Is there any difference in using the 3V or 5V line for my GPU through the adapter as opposed to the 12V?
 

 

 
My modular section all says V2 so I'm guessing that is using my 12V(2) while 12V(1) is used in the non modular section. I'm guessing that means that I can have thus one GPU plugged into 12V(1) with one of the cables that are left from the PSU's non modular part and then connect GPU2 with 12V(2)
 
Nov 24, 2013 at 6:18 PM Post #3,448 of 9,120
 
bowei006 said:
  Is there any difference in using the 3V or 5V line for my GPU through the adapter as opposed to the 12V?
 
My modular section all says V2 so I'm guessing that is using my 12V(2) while 12V(1) is used in the non modular section. I'm guessing that means that I can have thus one GPU plugged into 12V(1) with one of the cables that are left from the PSU's non modular part and then connect GPU2 with 12V(2)
Click to expand...

 
Yeah, you'll want to be using the red connectors if possible to plug in your second GPU. This is because they are all 12V pins, which will share the current load across the three of them.
 
There's only one 12V conductor on the other modular connections, and that might be a problem if you try and power a whole GPU from one of them, as the cable may exceed it's rated current capacity. If you have to use the 4-pin molex converter thingies, use 1 plug from each separate modular connector breakout. It won't be an issue at all, but lets avoid shoving 12A down one single 18awg conductor of questionable quality in a hot PC case. 
tongue.gif
 
 
Nov 24, 2013 at 6:21 PM Post #3,449 of 9,120
deadlylover said:
   
Yeah, you'll want to be using the red connectors if possible to plug in your second GPU. This is because they are all 12V pins, which will share the current load across the three of them.
 
There's only one 12V conductor on the other modular connections, and that might be a problem if you try and power a whole GPU from one of them, as the cable may exceed it's rated current capacity. If you have to use the 4-pin molex converter thingies, use 1 plug from each separate modular connector breakout. It won't be an issue at all, but lets avoid shoving 12A down one single 18awg conductor of questionable quality in a hot PC case. 
tongue.gif
 
Click to expand...

All of the modular 12V options seem to be tied to the 12V(2) which leads me to think that 12V(1) is the one that is non modular
 
So one GPU for each 12V rail?
 
You must log in or register to reply here.

Users who are viewing this thread

Total: 9 (members: 0, guests: 9)
Back
Top