Source of Problem

Des_Zac

Member
So I just got a 7870 a couple days ago and have been having some problems I want to find the source of. So, as seen in the pictures attached to this post at random times (This has happened twice now) The screen will go into a weird array of colors which will not stop until I reset the computer. I have checked the cables and, as it happens on both monitors, can't be the source.

I would immediately attribute it to a faulty graphics card and send it back immediately but here's the thing, this only happens on the monitor designated as monitor 1 in Windows. When both monitors are connected it only happens on monitor 1, and when I unplug the monitor set as 1 the secondary monitor becomes monitor 1 and it happens on that monitor.

I want to figure this out as soon as possible so I can send it back soon, but I can't tell if it's a GPU, driver, or windows problem.

Thanks,

-Zach
 

Attachments

  • aaa.jpg
    aaa.jpg
    19.2 KB · Views: 76
  • aaaa.jpg
    aaaa.jpg
    19.7 KB · Views: 70

johnb35

Administrator
Staff member
What make and model of power supply do you have? Have you tried updating the video drivers?
 

Des_Zac

Member
Sorry for the late reply, I just didn't have much time yesterday.


I'll include a picture but here's the basic info.

It's a 400w psu

I've tried finding information on this model but no luck in finding anything.

So, I'm gonna be ordering a new psu today or tomorrow, do you think I should just wait and test it out with that? I'd like input on this choice too but I should probably make a new thread for that in another section.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817152040
It's 80+ Bronze so I'd assume it's pretty good, don't plan on getting anywhere near 500w anyways.

Anyways here's the picture.

Model Number is VP-400
 

Attachments

  • aaaa.jpg
    aaaa.jpg
    16.5 KB · Views: 64
Last edited:

mr.doom

Member
Switch your power supply as fast as you can to a known brand like Corsair, Enermax or EVGA. It seems like not only you have too little watts, but also unstable power delivery. I would switch before you fry your card.
 

Des_Zac

Member
Switch your power supply as fast as you can to a known brand like Corsair, Enermax or EVGA. It seems like not only you have too little watts, but also unstable power delivery. I would switch before you fry your card.

Ha, that's what you'd think, this thing has been in several computers for over 4 years so it isn't terrible, I've honestly never had a problem before, and nothing bad has ever happened when using it, so that's why I thought it might not be the problem.

The xTreme psu calculator says I should have 305-355 watts for the system I'm using so I don't think under-powering is really the problem here though.
 

Des_Zac

Member
error 1: you believed a PSU calculator.
error 2: assumes that it has worked for years, so it can't be that bad. Length of service is not a sign of quality. You can have a high quality unit last a day, and a low quality unit last 50 years, it will not change teh parts inside.

Second, you have 240 watts (advertised) MAX power on the 12 volt rail, and just the 7870 and 2500k at load will draw 210 watts. You don't have enough power period.

I didn't say I assumed it wasn't bad, I just said it wasn't terrible, as in it has worked just fine. And I know not to completely rely on the PSU calculator, but that doesn't mean it's gonna give me COMPLETELY ridiculous numbers.

Back on topic, would having an underpowered PSU cause the specific problem I asked about? And what about the PSU I linked, would that be good for the situation I'm in?
 

johnb35

Administrator
Staff member
Yes, a bad power supply could be causing issues with the video card. You've got a 7870 so you should have about a 600 watt psu for headroom. Get the corsair cx600. The raidmax unit you linked is crap.
 

Des_Zac

Member
Yes, a bad power supply could be causing issues with the video card. You've got a 7870 so you should have about a 600 watt psu for headroom. Get the corsair cx600. The raidmax unit you linked is crap.

If you could, could you explain what exactly about the psu is bad? I've never really been able to understand the deciding factor in what makes a PSU bad.

I understand that most PSUs are basically rebranded PSUs ordered from manufacturers, Seasonic being the most highly held manufacturer correct?
 

johnb35

Administrator
Staff member
Raidmax is a cheap end unit. For an entry level pc with onboard video, it may survive a few years but when you are dealing with a video card such as a 7870 and other components, you don't want to be using that brand. The unit you linked only has 384 watts on the 12 volt rail. You aren't even close to where you need to be. The corsair cx600 has 522 watts on the 12 volt rail, which is where you need to be.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139028
 

Dean11

Member
Its an absolute POS. Throw it away. 14 amps on 12v rail is peanuts.. It can't supply the power you need to run that card, meaning it will run at 100% and that's not where these crap supplies are rated to run at. Meaning dirty power and fried components.

This problem you see is the graphics card giving in cause you ain't giving it enough juice.
 

johnb35

Administrator
Staff member
You really don't need anything higher than a 650 watt psu. Why spend over $100 when you can spend around $70?
 

mr.doom

Member
The basic is that - the wattage stated on the box is irrelevant. It is all about the PSU's effciency. If you have a 400W PSU with 80% efficiency (which you do not), the maximum power it can deliver is 320W. That goes for good power supplies. The cheap end power supply will have lesser efficiency and will be unable to deliver a stable current at a load. It doesn't matter how well it functioned in the older systems, they just simply weren't enough to push the PSU to its limit. Your new GPU does just that, and your PSU starts to send out an unstable current.

Please do not make a mistake that many made before - do not underestimate the importance of a good PSU. It is arguably THE most important component of any modern, stable PC - every other component depends on it. Here are my recommendations for you:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139048 - 79.99

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153168 - 89.99, Gold Certified - means best efficiency

http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 - 79.99
 

Darren

Moderator
Staff member
The basic is that - the wattage stated on the box is irrelevant. It is all about the PSU's effciency. If you have a 400W PSU with 80% efficiency (which you do not), the maximum power it can deliver is 320W. That goes for good power supplies. The cheap end power supply will have lesser efficiency and will be unable to deliver a stable current at a load. It doesn't matter how well it functioned in the older systems, they just simply weren't enough to push the PSU to its limit. Your new GPU does just that, and your PSU starts to send out an unstable current.

Please do not make a mistake that many made before - do not underestimate the importance of a good PSU. It is arguably THE most important component of any modern, stable PC - every other component depends on it. Here are my recommendations for you:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139048 - 79.99

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153168 - 89.99, Gold Certified - means best efficiency

http://www.newegg.com/Product/Product.aspx?Item=N82E16817371044 - 79.99


That's only partially true. It is has more to do with how much power is on the 12 volt rail. It's not hard to bump up how much wattage the PSU it has by adding it to stuff like SATA and Molex connector. The 12 volt rail powers the motherboard, CPU, and GPU, so it will be the most important by far in looking for a PSU.

I for one have the CX 600 and it works great for almost 2 years now with zero problems. There's a modular version out now that would help with cable management.

The OCZ you linked is good but way above what you need, but if it's on sale it wouldn't be a bad choice.
 

mr.doom

Member
That's only partially true. It is has more to do with how much power is on the 12 volt rail. It's not hard to bump up how much wattage the PSU it has by adding it to stuff like SATA and Molex connector. The 12 volt rail powers the motherboard, CPU, and GPU, so it will be the most important by far in looking for a PSU.

I for one have the CX 600 and it works great for almost 2 years now with zero problems. There's a modular version out now that would help with cable management.

The OCZ you linked is good but way above what you need, but if it's on sale it wouldn't be a bad choice.

I agree. It is safe to say that if you would be to choose your psu by the technicalities it is much to stomach. But, by a rule of a thumb, use the psu calculator and then add 200W to the result, provided you stick with a well known brand. If you plan on upgrading - double the recommended wattage.
 

spirit

Moderator
Staff member
Yeah I agree with some of the posts here - you definitely do not have enough power to run a 7870, and that's an end of it.

You need to upgrade. The OCZ unit you found is good, I use an OCZ ZS 650 in my system powering a 5870 (which is more power hungry than your 7870) and an overclocked i5 2500K and it's running great, so I'd trust OCZ. The Corsair units are also great. Something in the 600-650W range is what you want really. You can go higher, but it's not needed, so it's a waste of money. I wouldn't advise you go for anything lower than 600W though.

A Corsair CX 600 or TX 650 V2 would be ideal for you, and as Denther said, you can now get modular CX 600s which makes the CX 600 the bargain of the century really. :)
 

Okedokey

Well-Known Member
The basic is that - the wattage stated on the box is irrelevant. It is all about the PSU's effciency. If you have a 400W PSU with 80% efficiency (which you do not), the maximum power it can deliver is 320W. That goes for good power supplies. The cheap end power supply will have lesser efficiency and will be unable to deliver a stable current at a load.

That's only partially true.

Actually Denther none of that is true.

Firstly, efficiency doesn't work that way. If a computer requires 400W from a PSU that can deliver a 400W (33A DC) - a total of 480W (2A AC) will be drawn from the wall. Not the other way around ;)

Efficiency has nothing to do with stability. Vdroop will occur on a cheap or old PSU which can and will cause overheated and damaged VRAM which causes the above pic - but its not caused by efficiency. A purely side-effect is the heat it will produce, further derating the PSU.

The PSU has 12V ATX design limits 12V_1 to the CPU leaving the remaining 12A for the GPU, clearly insufficient.

240W is peak max 12V (20A).

20A on the 12v rail is insufficient for ANY discrete GPU in my opinion.

26A is my absolute minimum for safe usage.

But that 20A is PEAK MAX. Meaning if you get close, you get problems and eventually bang. Dead computer.

Derating it at 4oC per delta T above 25oC could further limit its ability by around 100W in summer.

You are killing your machine with a super super low end junk.

This is an awesome PC Power and Cooling PSU, is cheaper at $70 and has 38A CONTINUOUS on the 12V rail. Although the Corsair is cheaper, the PCPC is way better spec. Either are way more than you need with your computer.

It doesn't however mean you haven't done perm. damage already.
 
Last edited:
Top