2GB HD 6950 Confused about PSU and Rails

[tshaddz]

I posted this on the graphics forum as well cause i wasn't sure where I would get the best help.

I have a Rosewill Extreme RX850-S-B 850 W psu (not the best I know) I recently upgraded my GPU from a Radeon 5770 to a 2 GB Radeon 6950. Everything was great for about 1.5 hours but now sporadically the computer shutsdown and restarts. When this happenes it wont load passed BIOS and I have to manually turn off and back on then its fine until it happens again. My GPU temp is never above 60 degrees under load so far and CPU didnt go above 50.

When i went to take out the new card I noticed I actually have 4 6 pin connectors labeled PCIe for graphics card. 2 of them are labeled 12v1 and 2 are labeled 12v2. I think i goofed because I had 1 of each plugged in to the GPU. Is this my problem? Should I put both labeled 12v2 in? also for what its worth in the catalyst control center the battery icon next to the GPU temp icon was only half filled green? not sure what that means. I would appreciate any help.

 

[alvine]

you can try the 12v2. the psu connectors are made so you can't get plug them the wrong component. when I received my 6pin 8 pin card I was trying to connect the 8 pin power and it would not fit, shortly after I found out it was the 8 pin CPU power cable xD (modular psu)

 

[tshaddz]

I know I cant plug them in to the wrong component my question is my PSU is split between 4 rails. I have 4 6 pin connectors in total that can plug in to my gfx card. 2 are 12v1 and 2 are 12v2. My question is what ones should I plug in to the card? I think i goofed by plugging 1 of each which is causing system shutdowns. I read you should never hook 1 GPU up across 2 rails. Is that true and would doing so cause the issues I am having?

 

[4745454b]

Try the 12v2. I don't know where the mobo and CPU get their power from but it might be from 12v1.

Honestly if you can play for awhile (1.5hrs?) and then have a problem tells me its probably a heat issue. If your PSU is struggling to much to provide the needed power it might be tripping an over heat sensor or perhaps the voltage is going out of spec. A new PSU is probably needed.

 

[tshaddz]

to be honest its sporadic. 1 time it was 1.5 hours another time it was 10 mins. case didnt feel hot and GPU temp never went above 60

 

[4745454b]

But if the PSU was too hot....

 

[rufus_22]

I agree , sounds like the psu is the culprit . If it were the pin cons to the gpu you would have an immediate symptom . imo

 

[tshaddz]

I agree , sounds like the psu is the culprit . If it were the pin cons to the gpu you would have an immediate symptom . imo

so at this point should I just buy a new PSU or try hooking it up to a dedicated 12v2 rail. I looked at my PSU and its 4 rails at 20A totaling 768 watts or 64A. I wouldnt mind buying a single rail corsair PSU but still think it may be worth it to try running it off a dedicated rail first. I Have read other things where using 2 rails on 1 GPU can make it sporadically short and reboot.

 

[vrumor]

Have you tried your old card to see if it gives you issues? But most likely it is the PSU.

 

[tshaddz]

yea been using my old card for a year. with this power supply the last 2 months without an issue at all right up until i upgraded last night. I made sure I removed Drivers and installed new ones the proper correct way. Just came back from computer store and he looked at the specs of my PSU and saw it is in fact a dedicated 4 rail PSU and given the "specs" should handle what I have. He suggested its possible perhaps trying to run 1 wire from each rail was a mistake and could cause the card to draw too much power from rail 1 which is most likely powering the CPU and mobo and that I should try dedicated the GPU to rail 2. The worst that happens it shuts down which he said it could just be a bad PSU in terms of Watts it is actually outputting. Maybe it was enough for the 5770 but the 6950 requires 500w. On paper this PSU can do it but if its damaged it may not be able to. Sucks its only 2 months old, but if it happens after I try the dedicated rail I found a nice 850W Corsair PSU for $160.00 that is a single rail and good rating. im almost tempted to just buy it anyway.

 

[ETRacer]

Cross railing a PSU is not recommended in most cases. sounds like a your PSU.

Here is a good article on multi rail systems vs single rails.

http://www.antec.com/Believe_it/PSU/index.php

 

[rufus_22]

any chance the new card spikes over rail limit ?

 

[ko888]

Try the 12v2. I don't know where the mobo and CPU get their power from but it might be from 12v1.

Honestly if you can play for awhile (1.5hrs?) and then have a problem tells me its probably a heat issue. If your PSU is struggling to much to provide the needed power it might be tripping an over heat sensor or perhaps the voltage is going out of spec. A new PSU is probably needed.

Rosewill Xtreme RX850-S-B +12V Rail Distribution:

12V1 - 2x3 pin PCI-e x 2

12V2 - 2x3 pin PCI-e x 2

12V3 - 2x4 pin EPS 12V

12V4 - 20+4, SATA, peripheral, 3.5" power, 2x2 pin ATX12V

OCP trip point is set at 30 Amps on each +12V rail.

 

[delluser1]

yea been using my old card for a year. with this power supply the last 2 months without an issue at all right up until i upgraded last night. I made sure I removed Drivers and installed new ones the proper correct way. Just came back from computer store and he looked at the specs of my PSU and saw it is in fact a dedicated 4 rail PSU and given the "specs" should handle what I have. He suggested its possible perhaps trying to run 1 wire from each rail was a mistake and could cause the card to draw too much power from rail 1 which is most likely powering the CPU and mobo and that I should try dedicated the GPU to rail 2. The worst that happens it shuts down which he said it could just be a bad PSU in terms of Watts it is actually outputting. Maybe it was enough for the 5770 but the 6950 requires 500w. On paper this PSU can do it but if its damaged it may not be able to. Sucks its only 2 months old, but if it happens after I try the dedicated rail I found a nice 850W Corsair PSU for $160.00 that is a single rail and good rating. im almost tempted to just buy it anyway.

Try not to ask him any psu question's
Having the power draw spread out over 3 rails ( power is also provided by the slot ) would keep it from overloading one.

Seriously sounds like you need a new psu.
PS; Don't know the rest of your specs but a good quality 550 watt psu will do for most single card systems.

 

[delluser1]

Cross railing a PSU is not recommended in most cases. sounds like a your PSU.

Here is a good article on multi rail systems vs single rails.

http://www.antec.com/Believe_it/PSU/index.php

Only way to get around it when using a multi rail psu is to use a card that doesn't require external power.
That article is as bad as the old PCP&C myths page that stated the opposite.

 

[tshaddz]

Try not to ask him any psu question's
Having the power draw spread out over 3 rails ( power is also provided by the slot ) would keep it from overloading one.

Seriously sounds like you need a new psu.
PS; Don't know the rest of your specs but a good quality 550 watt psu will do for most single card systems.

So could it be a coincidence my PSU went bad same night I installed this new card or maybe it was already bad and not pushing it enough to cause errors? Previously was using a 1GB Radeon 5770 (use to overclock)

My set up is
1 HD
1 DVD Drive
4 x 2GB Ram
AMD Phenom 1100T x6 processor
maybe 4 or 5 fans cant remember
Pending: ICE Q Turbo 2GB Radeon HD 6950

So I guess there is no point in trying to run a dedicated rail just on that graphics card seeing how those 2 rails apparently aren't powering anything anyway. Maybe Ill stop on my way home and pick up a new PSU and not open it and try anyway... how is this PSU

Corsair TX850 Enthusiast
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139022&Tpk=corsair tx850



only thing I plan on doing after this card is running eyefinity

 

[ko888]

The Radeon HD 6950 has a Maximum Board Power of 240 Watts.

The Radeon HD 5770 has a Maximum Board Power of 108 Watts.

The power draw has essentially doubled when you upgraded.

 

[delluser1]

So could it be a coincidence my PSU went bad same night I installed this new card or maybe it was already bad and not pushing it enough to cause errors? Previously was using a 1GB Radeon 5770 (use to overclock)

My set up is
1 HD
1 DVD Drive
4 x 2GB Ram
AMD Phenom 1100T x6 processor
maybe 4 or 5 fans cant remember
Pending: ICE Q Turbo 2GB Radeon HD 6950

So I guess there is no point in trying to run a dedicated rail just on that graphics card seeing how those 2 rails apparently aren't powering anything anyway. Maybe Ill stop on my way home and pick up a new PSU and not open it and try anyway... how is this PSU

Corsair TX850 Enthusiast
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139022&Tpk=corsair tx850



only thing I plan on doing after this card is running eyefinity

Pretty good, and way more than you need.
You gave a Newegg link, picking up from there ?

 

[tshaddz]

The Radeon HD 6950 has a Maximum Board Power of 240 Watts.

The Radeon HD 5770 has a Maximum Board Power of 108 Watts.

The power draw has essentially doubled when you upgraded.

correct I am well aware of that and on paper my PSU should be able to handle the 6950. what I was questioning was is it possible my PSU was under performing all along but because of the 5770 not requiring as much it was never an issue?

 

[ko888]

correct I am well aware of that and on paper my PSU should be able to handle the 6950. what I was questioning was is it possible my PSU was under performing all along but because of the 5770 not requiring as much it was never an issue?

The Rosewill Xtreme RX850-S-B should have had no problem handling the Radeon HD 6950 if it the PSU is functioning properly.

It should have been able to handle two Radeon HD 6950 running in 2-way CrossFireX mode.

 

[tshaddz]

Pretty good, and way more than you need.
You gave a Newegg link, picking up from there ?

yea normally I would but there is a micro center down the road from my work. Its a little more money but I will probably grab it from there so I can install and test it tonight. I am pretty bummed out about it and too impatient to wait for shipping lol. I am the type of person that understands things not working but hates not knowing why or what caused it.

 

[tshaddz]

reading on the internet im getting a little scared it could be something more serious like the mobo. When this shutdown happens it tries to restart but freezes at the bios screen. everytime its done this i just turn it off turn it back on and do my thing. sometimes it goes another hour one time it last like 15 minutes. I am assuming if it was a mobo or other device issue things wouldnt load at all. I guess what I am trying to say is before I buy a new PSU how sure can we be that it is the problem? Again built this PC myself a year ago and never ever an issue until i installed the card last night.

 

[ko888]

Have you checked your Windows Event Viewer for any Error or Warning events in the System events that may give you an indication of what may be causing it?