No video on boot

[casacase]

Dear all,

First of all, I am new member and have been reading through these forums for all kinds of technical advice. This community has been of great help. This is why I turn to you guys with a challenge which I haven't been able to find the answer for after 4 days of googling and testing.

I am working to apply a minor upgrade to my brothers system so he can reach acceptable framerates on his favorite games (still not done though). I have replaced the mobo, graphics card, ram, cpu + decent heatsink (for OC purpose after this problem).
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My problem is the following:
I get no display on boot, the system is booting fine I just don't get any video signal. The monitor is aware of the cable being connected but still I only get a black screen. With the graphics card which he had running on his original configuration everything is working fine.

steps taken:
- Checked all cables for damaged connection.
- Updated BIOS to the latest version +modded bios hoping for improved compatibility.
- Reset CMOS
- Tested GTX275 in my friends + old system.. in both cases it worked. The card works fine.
- de-install windows drivers of GT7800 (I know it doesn't have anything to do with no video on boot but I got desperate)
- Disconnected all devices except the necessary ones to rule out insufficient power
- Screwed with every PCI-e related BIOS setting to no avail (I still feel the problem lies in the BIOS settings, but don't know where to look for it anymore)
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specs:
MB: P5QL-pro
CPU: E8400 @3ghz
GPU: Geforce GTX 275 1GB (old "working" card = Geforce 7800GT)
Ram: 2x2gb DDR2 800mhz
PSU: 500W Coolermaster RP-500-PCAP (This will be upgraded for optimized efficiency on PSU)

I am really desperate to get this thing running. I go to bed trieing to see the big picture on my missing step and I wake up in the same "problem isolating" state of mind.

HELP ME PLEASE!

 

[casacase]

PLEASE!

Does anyone has any suggestion?

 

[Hinda65]

so.....are you saying you get video on the new build with the 7800 and not the 275?

only thing I can think of is a problem with your 6pin power connectors....do you have another psu you can try? the 275 takes (2) connectors and the 7800 takes (1)...right?

 

[casacase]

correct. The new build with the 7800 is working great.

While the 2x6-pins power are connected properly to the GTX275, the system doesn't give any image but still boots into windows from what I can hear.

 

[Hinda65]

I'm seeing Coolermaster RP-500-PCAP only has (1) 6pin pcie connector? I'm also seeing the 275 needs a minimum 550w psu and 40 amps on the 12v...you need a bigger psu.

 

[casacase]

correct Hinda, I've purchased an adapter (double 4-pins molex to 6-pins pci-e power) to feed the card.

I've read the same about the minimum requirements on the 275. BUT the strange thing is... I've bought this card before the mobo upgrade... That was a nforce 650i ultra, 2x1gb, E6750 system. On that system (with the exact same PSU) the graphics card didn't have any trouble. It worked perfectly. When it wouldn't work I dug into the power consumption of my new mobo and it's nearly similar. Further more I disconnected all excess components to try and feed the card enough power when connected to the new board. That didn't work.

I've read several of threads about insufficiently powered graphics cards.. All the time they work but they start to act jerky. I've not read anything about failing GTX cards on a 500w PSU. Power calculators didn't get me to 450w on minimal component configuration.

I have to admit you are right I have to upgrade the PSU. But it should at least give an image on minimal settings.

 

[casacase]

Is there anyone online who can help me with this?

 

[jkauff]

I assume you've tried a different PCI-e slot (if you have one).

I wonder if your power connection will end up being the problem. Does your card have an LED for each power connection, and are they both lit and green? Have you tried not using the pci-e power cable at all, and using two adapters instead? Your PS has two 12v rails, maybe the SATA plugs and the molex plugs are on different rails.

I only ask because the symptoms are so similar to what happens when the GPU isn't connected properly to the PS.