GPU power source question - Techist - Tech Forum

Go Back   Techist - Tech Forum > Computer Hardware > Overclocking and Modding
Closed Thread
Thread Tools Display Modes
Old 07-12-2006, 07:03 AM   #1 (permalink)
Master Techie
Join Date: Jun 2005
Posts: 2,134
Default GPU power source question

when a GPU is plugged into a 6-pin power source, does it get 100% of its power through this, or does it still recieve some power through the pci-e bus?

i am planning on getting a 7900GT, but as the dell only has a 305W psu, i am planning on using an old 145W PSU for the GPU alone. i am assuming that it would power it ok.

i tried googling, but dont really know what to search for. i just get info that some need the power connector, not anything that shows how it actually works.

joshd is offline  
Old 07-12-2006, 07:52 AM   #2 (permalink)
Enterprise SCCM\SCOM
jseber1982's Avatar
Join Date: Sep 2004
Location: Atlanta, Ga
Posts: 904
Send a message via ICQ to jseber1982 Send a message via AIM to jseber1982 Send a message via Yahoo to jseber1982

so you are going to use a separate psu just for the gpu? First thing you will need to do is jumper a wire on the mainboard power connector on it so it will turn on. And does that psu have a connector for a pci-e card? And if not,, your planning to splice and solder wires to make it?

And another thing, from what i have read and heard on many forums... powering a psu up without it actually connected to the mainboard can damage stuff because the psu is built to have a certain load on it.

How new is your dell???
The OLD OLD dells use regular atx power supplies.. the old ones use proprietary power supplies.

The newer ones like the 620 and stuff use standard atx. At my work i put a 650w psu in a gx620 and use it as my lunchtime gaming box.

You also might want to look online to see how to mod an atx psu to use in a dell box.

Using 2 psus like that sounds really risky to me.. All you need is a small voltage leak and you could possibly loose both psu's, and other stuff like your gfx card or mobo.

jseber1982 is offline  
Old 07-12-2006, 08:02 AM   #3 (permalink)
Master Techie
Join Date: Jun 2005
Posts: 2,134

mine uses an ATX, but i would rather not have to buy one, i cant afford a PSU AND a 7900gt.

yes, psus often have a minimum draw, but this will be satisfied by the GPU no problem.

yes, i will just stick a wire on the mobo connector. done that before, it works fine.
joshd is offline  
Old 07-12-2006, 11:16 AM   #4 (permalink)
Monster Techie
Ridlyn's Avatar
Join Date: May 2005
Posts: 1,920

Good luck, be prepared to get some extra cooling, because it's gonna get hot in those dell cases. With my stock cooling on my 6800 in a dell case got to over 100ºC, then i got my zalman vf700-cu and temps never go above 60ºC. I also had to add a pci slot cooler and a make a new hole for 120mm fan on the side.
Originally Posted by Sylus View Post
Could have been worse, you could have been raped by a clown.
Ridlyn is offline  
Old 07-12-2006, 12:19 PM   #5 (permalink)
Master Techie
Join Date: Jun 2005
Posts: 2,134

@ Ridlyn

well, the side will be off all the time due to the wires from the 2nd PSU. i think it will be cool enough. i believe the 7xxx series dont run as hot at the 6 anyway.
joshd is offline  
Old 07-12-2006, 11:31 PM   #6 (permalink)
True Techie
Join Date: Mar 2006
Posts: 190
Send a message via AIM to the yellow one

just get a good PSU because if you're new to this you are all worry and crap and if did it wrong you could damage your computer. so just get a good one.
I am the yellow one.
the yellow one is offline  
Old 07-13-2006, 12:31 AM   #7 (permalink)
Hard Gay Nahalem! Fooo!
NosBoost300's Avatar
Join Date: Nov 2005
Location: Bellflower, CA
Posts: 10,154
Send a message via AIM to NosBoost300

i'm sure the one you have will do fine.. i did the same thing with a 450 watt for 2 7900 gt's worked like a charm
Current Build:
Intel 3770k @ 4.4 GHZ | Galaxy GTX 770 SLi | 16 GB G.Skill Sniper | ASrock z77 Extreme4
2xSamung 840pro 128GB in Raid | 2x1TB Seagate | Antec 750 Watt GamerSeries
Media Build:
Intel Core i3 3220 | Galaxy GTX 650 | 8 GB Corsair Vengeance | ASrock B75M | Samsung 840 120GB
NosBoost300 is offline  
Old 07-13-2006, 12:38 AM   #8 (permalink)
Build Guru
PP Mguire's Avatar
Join Date: Dec 2004
Location: DFW Texas
Posts: 26,034

Undervolting certain things will end up in frying them in the long run. Never undervolt your cards or processor. Always have a suffiecient PSU becasue you will be paying for more than just a PSU ounce things start to cook.
"Resolution is just a number." #Ubisoft Origin/Steam = PP_Mguire Twitch = pp_mguire Instagram = ppmguire Mechwarrior Online = Thunderson PSN = PP_Mguire

Need Descent and Mechwarrior buddies!
If I helped you, give a thanks! ↓
Access to my Plex PM me.
PP Mguire is online now  
Old 07-13-2006, 03:12 AM   #9 (permalink)
Master Techie
Join Date: Jun 2005
Posts: 2,134

well, a multimeter on my 12v rail already shows only 10.5v... i am not sure if this is correct, as i dont think a computer would even boot at that?
joshd is offline  
Old 07-13-2006, 06:10 AM   #10 (permalink)
Wizard Techie
CrazeD's Avatar
Join Date: Feb 2006
Location: Maine
Posts: 3,736
Send a message via AIM to CrazeD Send a message via MSN to CrazeD

Make sure your multimeter is set right..


Intel Q9400 | Gigabyte EP45-UD3P | G.Skill 2x2GB DDR2 1000 | XFX HD5870

Need website help? PM me!
CrazeD is offline  
Closed Thread

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are Off

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 10:52 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.