How I Tell If I Need a Bigger Power Supply?

photoman11 used Ask the Experts™
My PC is an HP e9150t quad core desktop using an Intel i7 CPU (920@2.67 GHz). I have 8 GB of RAM and am running Windows 7 Home Premium-64-Bit. It was purchased new from HP, in July 2009. The Microsoft products I am running include the 2007 versions of Outlook, Word, and Excel.

Since having my computer for the last year, I have had various problems from BSOD to upgrading from Vista to Windows 7. Using deductive reasoning and a lot of help from Expert Exchange, it seems that most of the issues/problems revolve around having added a 2nd video card to my PC.

Having discovered that my particular HP model may be the non-automotive equivalent of a lemon, also doesn't help much. I added a 2nd video card because in addition to 2 monitors that I run off the primary video card I upgraded to when I purchase my machine (the ATI radian HD 4650), I wanted to connect to an HDTV, which could not be done  with my current video card.

It seems that there is a high correlation between computer crashes/BSODs and watching the HDTV, which is connected to the 2nd video card-ATI radian HD 4550.

Based on suggestions from ATI and about 3 other sources, I removed the side panel to my computer and placed a small fan directed at the boards. This has proved surprisingly effective in stopping crashing and BSODs.

Not knowing what the potential long-term negative ramifications may be on my system, it has been suggested that with the number of peripherals I'm running and the inherent issues there may be with my particular computer model, I should consider going to a larger power supply.

This is completely out of my experience level, so I am trying to get some opinions on whether or I should consider installing a new power supply and/or fan, or just leave well enough alone since it seems to be working okay with my current setup.

For reference, my current PC has 2 internal drives - a 1.5 TB drive and a 750 GB drive. I also have the following externals: (1) 1 TB eSATA drive, (1) 1 TB drive, (1) 750 GB drive, (1) DVD R/RW optical drive (in addition to the one internal optical drive). Although most of the following components are not on all of the time, I have 1 laser printer, 1 color DeskJet, and 1 color photo printer. In addition, there is a Bluetooth dongle for syncing my Palm smartphone.

Thank you and much for any help and opinions. The
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On a side note: The peripherals (monitors, printers, speakers etc.) aren't really significant since they have their own power supplies.
I would test the display adapters for overheating issues. I use FurMark, you can get it here. 
Robert RComputer Service Technician
Asus has a good tool to find out what kind of powersupply you require:
I read through this thread ( From the sounds of it, it could possibly be the ram (vendor). I would check with the motherboard vendor and find their recommended list of ram. With ASUS (I have a p5N-D), they have a list of recommended or supported ram chips. There have been a lot of purported blue screens and lock ups with that model. I would suggest though putting in water cooling for that i-7. They tend to run pretty hot.


Thanks everyone Than the process of doing the area status and/or contacting the recommended people to follow up on this.

Wolfhere, I started reading that thread again (I've read various pieces of it off and on the last 6 months), but I could never get past 5 or 6 pages because of all the tears in my eyes.

Let me ask you these questions, realizing that I am not real hardware-literate...

1. Are you saying that the motherboard and the RAM that HP used to build  my system may not be compatible?! If that's the case, how would I find definitive proof of this, since my warranty is over in about one day.

You mentioned suggesting putting in water cooling. Reiterating the fact that I do not know that much about hardware, that sounds like a major adventure; am I correct?

Thanks everybody. I will post the results of my tests, over the next 24 hours hopefully.
Top Expert 2013

you can easily check if the temperature is a problem : install speedfan to monitor  :

i would be surprised if HP sent out incompatible hardware...but everything is possible

I just read the first 40 pages in reference to your machine from the HP forum that is listed above.

Some of the areas are listed below:
From page:

I know that you have read 5 or so pages of the HP and it was not good to you. I am sorry for you having been caught in the issue of the HP / Pegathron  mess up. It appears that the problem is related to the Pegathron motherboard, HP Power supply being too small, not having enought case cooling and version of Intel CPU. I believe that your machine is just not well designed by HP trying to get to market.

I can not suggest that you contact HP support and insist on being given a full refund. But I would if I had paid large money for a good computer and not get it. I am sorry that I can not provide a good working repair suggestion.

All the best to you.


And the beat goes on...

I actually have speed fan version 4.40, but really don't know what I'm looking at (now that's a surprise, right?). Is there some log or report I can get that tells me something?

All things considered with the 9150 debacle, my machine isn't too bad. At least, it does not continually freeze up.

I feel guilty taking up anymore of your time with this HP sinkhole, or should I say stinkhole? is there any way to get a "bottom line" here?

Currently, I'm running with the 1.03 version of the Pegathron motherboard, and the originally installed PSU. I have the side panel off and a small fan directed into the PC. If memory serves me (which it has not been doing very well), I believe for the last month, whenever I have the fan going, regardless of what else is happening, I HAVE NOT EXPERIENCED a BSOD.

Therefore, in my non--hardware literate brain, I see these options:

1. Keep praying to the computer gods and don't do anything other than waiting for this computer to become obsolete and then get a new DEFINITELY NOT HP computer

2. Replace the PSU with a larger one, but how large I have no idea

3. Replace the motherboard

4. Replace the PSU AND the motherboard

5. Contact HP (although I really don't know what this politically motivated group of Buck-passers would do, other than waste a lot more of my time)

6. Hope the class-action lawsuit reaches a speedy conclusion (like that's going to happen) and I could take the $15 I would get and try to find an HP executive bending over to tie his shoes and I can insert the $15... (use your imagination)

I actually remember when HP used to be a good company.

Speedfan is fine for monitoring temperatures but if you don't stress the components it won't really tell you much. You suspected one of the display adapters that's why I suggested FurMark to test them. Running FurMark stress test will let you know that in a short time.


The reason I did not use FurMark was that it stated:

"This benchmark requires an OpenGL 2.0 compliant graphics card: NVIDIA GeForce 5/6/7/8 (and higher), AMD/ATI Radeon 9600 (and higher) or a S3 Graphics Chrome 400 series with the latest graphics drivers."

In my graphic cards are the ATI Radeon 4650 and 4550, which I assumed are not equal to or higher than the 9600. The other reason is that I couldn't find a download version that was anything other than 32-bit.
Top Expert 2013

if you just run your pc, you'll see the speedfan temps varying.
Once it moves into the red flame, verify the max temp for your CPU, disk or video chip
if it stays green - no problem from that side.


According to the postings from the HP forum,  the problem usually showed up on power up. I did read that the HP responses were to exchange the old computer with a new one and the new computer had a newer motherboard installed. The posts indicate the motherboard was a v1.04. They also indicated that the replacement machines were doing much better. I believe that this is moving in the right direction but is not completed. The forum posts:, is currently at 375 pages.and seem to indicate the the best solution is to upgrade the video card to a GTX 470, install a new 700W PSU, and a new CoolerMaster case. all my freezing and lag problems have stopped since i'm offically DONE here and with HP

Hope that this helps



With an extremely low load, the cores ranged from 106F to 120F (110F = 43.3C).  From the CPU chart attached, my take is it's ok temp wise. Is this accurate?


Was the comment "upgrade the video card to a GTX 470, install a new 700W PSU, and a new CoolerMaster case. all my freezing and lag problems have stopped since i'm offically DONE here and with HP " something you got from the forum or do you have the same HP model?
Top Expert 2013
the max temp for i7 is 100°C :
so 42 looks good


The comment was condensed from the forum link that I had pasted into my post. I do not need that powerful of a computer.


thanks for everything

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