Bitcoin Forum
March 29, 2024, 12:45:51 PM *
News: Latest Bitcoin Core release: 26.0 [Torrent]
 
   Home   Help Search Login Register More  
Pages: [1]
  Print  
Author Topic: Maximum # of 7970 GPU's a Lepa 1600 PSU Can Handle ?  (Read 2570 times)
forexmasterja (OP)
Full Member
***
Offline Offline

Activity: 130
Merit: 100



View Profile WWW
June 23, 2013, 05:10:11 PM
 #1

Hey,

I have been reading alot of articles here mentioning Lepa 1600w PSU's for rigs over 5 cards.

I'm wondering if this PSU would be able to handle 5-6 7970 GPU's for mining both bitcoin and scrypt ?

Anyone have personal experience with this number of 7970's ?

--** First Jamaican Bitcoin User **--
1JamaicaYQvsBkvm5JcurQBA9Kz969nsqe
Revolutionary Money Making Cloud Miner - https://cex.io/r/0/forexmasterja/0/
1711716351
Hero Member
*
Offline Offline

Posts: 1711716351

View Profile Personal Message (Offline)

Ignore
1711716351
Reply with quote  #2

1711716351
Report to moderator
1711716351
Hero Member
*
Offline Offline

Posts: 1711716351

View Profile Personal Message (Offline)

Ignore
1711716351
Reply with quote  #2

1711716351
Report to moderator
It is a common myth that Bitcoin is ruled by a majority of miners. This is not true. Bitcoin miners "vote" on the ordering of transactions, but that's all they do. They can't vote to change the network rules.
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction.
1711716351
Hero Member
*
Offline Offline

Posts: 1711716351

View Profile Personal Message (Offline)

Ignore
1711716351
Reply with quote  #2

1711716351
Report to moderator
1711716351
Hero Member
*
Offline Offline

Posts: 1711716351

View Profile Personal Message (Offline)

Ignore
1711716351
Reply with quote  #2

1711716351
Report to moderator
BlazinBeaches
Member
**
Offline Offline

Activity: 98
Merit: 10


View Profile
June 23, 2013, 05:14:42 PM
 #2

My 6 7970s with mobo/cpu/ram/etc suck 1600+/- watts from the wall.  I would do 5 max on that psu unless you have a separate psu for mobo/etc.  But that's still cutting it close.  However you configuration try to leave at least 15% breathing room for the psu.
forexmasterja (OP)
Full Member
***
Offline Offline

Activity: 130
Merit: 100



View Profile WWW
June 23, 2013, 05:22:28 PM
 #3

My 6 7970s with mobo/cpu/ram/etc suck 1600+/- watts from the wall.  I would do 5 max on that psu unless you have a separate psu for mobo/etc.  But that's still cutting it close.  However you configuration try to leave at least 15% breathing room for the psu.

Ok cool sounds like it will do 5 easily then, whats your setup ? Mboard & cpu ?

--** First Jamaican Bitcoin User **--
1JamaicaYQvsBkvm5JcurQBA9Kz969nsqe
Revolutionary Money Making Cloud Miner - https://cex.io/r/0/forexmasterja/0/
PeeJWeeJ
Newbie
*
Offline Offline

Activity: 49
Merit: 0


View Profile
June 23, 2013, 10:46:24 PM
 #4

A 7970 can take 300 W. (75 from pci-e, 75 from 6pin and 150 from 8pin). If you want to run 5 cards on a 1600W power supply make sure your MB, CPU and RAM use as little power as possible since you potentially only have 100W of guaranteed headroom.
grobbes
Member
**
Offline Offline

Activity: 60
Merit: 10


View Profile
June 23, 2013, 10:58:01 PM
 #5

7970s are voltage unlocked so drop it to 1000 mV and adjust clocks and you should have no issue with 6. I run 4x7950s locked voltage under 1000w.
systic
Member
**
Offline Offline

Activity: 84
Merit: 10



View Profile
June 24, 2013, 02:09:02 AM
 #6

I had to decide recently myself and went with 2 psu's. ne 60$ silver 750 for 1x7970 and mobo/cpu and another rosewill 1300 for 2x7950s and 2 7970s. Total was 260$ new from newegg for pus power.
PeeJWeeJ
Newbie
*
Offline Offline

Activity: 49
Merit: 0


View Profile
June 25, 2013, 02:03:35 AM
 #7

I had to decide recently myself and went with 2 psu's. ne 60$ silver 750 for 1x7970 and mobo/cpu and another rosewill 1300 for 2x7950s and 2 7970s. Total was 260$ new from newegg for pus power.

I use the same rosewill PSU, it's worked like a dream and at an insanely good price!
forexmasterja (OP)
Full Member
***
Offline Offline

Activity: 130
Merit: 100



View Profile WWW
June 25, 2013, 02:06:15 AM
 #8

I had to decide recently myself and went with 2 psu's. ne 60$ silver 750 for 1x7970 and mobo/cpu and another rosewill 1300 for 2x7950s and 2 7970s. Total was 260$ new from newegg for pus power.

I use the same rosewill PSU, it's worked like a dream and at an insanely good price!

How many cards are you running though ? and are you using 2 psu setup like he mentioned ?

--** First Jamaican Bitcoin User **--
1JamaicaYQvsBkvm5JcurQBA9Kz969nsqe
Revolutionary Money Making Cloud Miner - https://cex.io/r/0/forexmasterja/0/
meowmeowbrowncow
Sr. Member
****
Offline Offline

Activity: 322
Merit: 250



View Profile
June 25, 2013, 02:14:12 AM
 #9




The Lepa 1600 has 2 20 Amp rails and 4 30 Amp 12V rails.


I would imagine this to mean that the 2 20 amp rails are limited to 240 Watts each.


The problem this leads to is that 160 Amps at 12V is well over the 1600 Watt rating for the PSU.  So, there is a limitation being obscured by the fact it has multiple rails.



The multiple rail business complicates a setup - so Lepa isn't as attractive to me.

"Bitcoin has been an amazing ride, but the most fascinating part to me is the seemingly universal tendency of libertarians to immediately become authoritarians the very moment they are given any measure of power to silence the dissent of others."  - The Bible
PeeJWeeJ
Newbie
*
Offline Offline

Activity: 49
Merit: 0


View Profile
June 25, 2013, 02:18:24 AM
 #10

I had to decide recently myself and went with 2 psu's. ne 60$ silver 750 for 1x7970 and mobo/cpu and another rosewill 1300 for 2x7950s and 2 7970s. Total was 260$ new from newegg for pus power.

I use the same rosewill PSU, it's worked like a dream and at an insanely good price!

How many cards are you running though ? and are you using 2 psu setup like he mentioned ?

4x 7950s along with the MB. I haven't seen better for $260.
forexmasterja (OP)
Full Member
***
Offline Offline

Activity: 130
Merit: 100



View Profile WWW
June 25, 2013, 03:32:06 AM
 #11

My Lepa 1600 work with 4x7990 - can push up to 1800W in long term and up to 2000W in short (at wall).

Now this is really getting confusing on the one hand have you saying you have 4x7990 working but that previous post about the multiple rails has me confused.

How exactly does the multiple rails affect the system setup when doing like 6 cards ?

--** First Jamaican Bitcoin User **--
1JamaicaYQvsBkvm5JcurQBA9Kz969nsqe
Revolutionary Money Making Cloud Miner - https://cex.io/r/0/forexmasterja/0/
mirny
Legendary
*
Offline Offline

Activity: 1108
Merit: 1005



View Profile
June 25, 2013, 08:03:24 PM
 #12

My Lepa 1600 work with 4x7990 - can push up to 1800W in long term and up to 2000W in short (at wall).

good to know i'm planning to connect 3x7990 to Lepa 1600W or Enermax 1500W or Master Cooler 1500W
actually wich 7990 are you using, gigabyte, msi, asus or sapphire?
and if it's not a secret how many mHash/s is it pulling?

This is my signature...
crazyates
Legendary
*
Offline Offline

Activity: 952
Merit: 1000



View Profile
June 25, 2013, 08:39:45 PM
 #13

My Lepa 1600 work with 4x7990 - can push up to 1800W in long term and up to 2000W in short (at wall).
Now this is really getting confusing on the one hand have you saying you have 4x7990 working but that previous post about the multiple rails has me confused.

How exactly does the multiple rails affect the system setup when doing like 6 cards ?
Actually those two go hand in hand pretty well. There are 4 rails that supply 30A each. If you hook up each 7990 to it's own 30A rail, you're all set.

Tips? 1crazy8pMqgwJ7tX7ZPZmyPwFbc6xZKM9
Previous Trade History - Sale Thread
forexmasterja (OP)
Full Member
***
Offline Offline

Activity: 130
Merit: 100



View Profile WWW
June 25, 2013, 10:18:30 PM
 #14

My Lepa 1600 work with 4x7990 - can push up to 1800W in long term and up to 2000W in short (at wall).
Now this is really getting confusing on the one hand have you saying you have 4x7990 working but that previous post about the multiple rails has me confused.

How exactly does the multiple rails affect the system setup when doing like 6 cards ?
Actually those two go hand in hand pretty well. There are 4 rails that supply 30A each. If you hook up each 7990 to it's own 30A rail, you're all set.

Ok but as it relates to the 6 7970's are you saying the multiple rails on the Lepa is bad ?

--** First Jamaican Bitcoin User **--
1JamaicaYQvsBkvm5JcurQBA9Kz969nsqe
Revolutionary Money Making Cloud Miner - https://cex.io/r/0/forexmasterja/0/
spawnbsd
Newbie
*
Offline Offline

Activity: 13
Merit: 0


View Profile
June 26, 2013, 09:16:02 PM
 #15

I'm use a VTX 7990 (I think is the same as powercolor). 4x7990 hashing ~ 4600 Mh/s in scrypt with this setings: core 835 @ mem 1375. My first 4 cores are undervolted to 0.925 and second 4 is default voltage (not accesible at bios).
Not trying to take this thread off topic, but I'm looking at building a similar setup with 4 * 7990. What OS are you using ? How are you cooling them ?
crazyates
Legendary
*
Offline Offline

Activity: 952
Merit: 1000



View Profile
June 27, 2013, 03:34:32 AM
 #16

Actually those two go hand in hand pretty well. There are 4 rails that supply 30A each. If you hook up each 7990 to it's own 30A rail, you're all set.
Ok but as it relates to the 6 7970's are you saying the multiple rails on the Lepa is bad ?
Potentially. Depends on how hard those 20A rails are being pushed.

Tips? 1crazy8pMqgwJ7tX7ZPZmyPwFbc6xZKM9
Previous Trade History - Sale Thread
xide
Member
**
Offline Offline

Activity: 88
Merit: 10


View Profile
June 27, 2013, 10:01:50 AM
 #17

one 7970 on LTC or scrypth depends on gpu/vram clock can spend even 350w
if you plan scrypth mining max 5  cards for lepa 1600 with undervolted...
before you buy cards check if there arent voltage locked ...new series with BE -BOOST EDITION most are locked..



BTC: 1L3ZAawXD3NxH82CSF241ZNQBS25ovNZtb LTC:LMyCbS4hmmoQyBn3LNRxydsECDWoKbdL2V PPC:PEZFPZmzoVe7STyQrjgBa943dzmLHim1uo FTC:6g2rnASKaPmVvPmtJG5b4MnAWz8XSgwpVs
NMC: My7Ee36vC4eR1Pk1ucqZCMNXBpuL7SNbvZ tnx for donations!
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!