Faulty mobo or graphics card problem?

  Catastrophe 11:23 08 May 2009

I posted a problem some time ago where there was no POST and the monitor light just blinked. The mobo came in a Lian Li case and the eBay vendor did not know whether mobo was functional so was not included in sale. Fair enough - I knew mobo might not work. CPU was new (eBay vendor had not used it as speed was not what he wanted. RAM was new from Crucial. Mobo was Asus P4P800-X.

Net result was mobo probably the cause of the problem. I have just received a new P4P800-SE (same requirements) and the problem is still there.

I tried several graphics cards including ones which worked in other PCs. Now I usually had built in graphics or used the card which came with the PC. Ones I had built previously always had built in graphics. So I know NOTHING about graphics cards.

Checking the manual carefully I saw that this mobo must have AGP BX14? 8J4? cards which MUST BE 1.5 volt. Now the cards I tried might be something else. Is it 3 or 3.3 volt? If I put in
3(.3) volt cards could this cause the problem? Would it cause any damage?

Comments gratefully received.


  xania 11:45 08 May 2009

AGP is a bitold hat now but come 4 speeds : normal,x2 (times 2), x4, x8

click here for more info.

So far as I am aware, each cards has its slightly different fitting so you cannot fit the wrong one, but to be perferctly sure you need to check your Mobo manual. P4P800-SE has I AGPX8 slot (which is 1.5 volt), but, as long as you are using An AGPx* card, you should have no problem. However, I'm wondering if you are looking in the wrong direction. If you have the same problem with a new mobo, and the graphiocs card fits properly, next step must be to check your monitor and its cable.

  nufc2009 12:08 08 May 2009

Is your power supply ok?

  Catastrophe 13:02 08 May 2009

Many thanks for your comments.


Some cards will fit in 'wrong' slots. For example in another PC I have a card with 3 slots which will fit the mobo in question which only has two ridges i.e., there is no notch to fit the other slot. The card works perfectly in its 'own' PC.

I have checked the manual which is where I found the 1.5 volt reference.

The monitor (and cable) work perfectly with other PCs.


Sorry, I forgot to mention the PSU. It is new and the PC powers the fans. Also the light comes on on both mobos.

  xania 14:40 08 May 2009

Yes - those slots are to ensure that you can only fit the card into a mobo that its is supposed to work in. So, if it fits, its safe.

So, the monitor works, because you've successfully tested in with another PC; the video cards work because they work with another mobo which only leaves the motherboard and you've already tried with an old one and a new one. I'm running out of ideas. I presume the video card is fully seated in the slot - sometimes when you get a new one it can be a bit stiff. Have you tried your new graphics card in another PC? I suppose is just possible that you bought a bogey? Also please check in Device Manager that you don't have any problems with display adaptors or with the monitor.

Otherwise, with end-to-end checked and working, I simply don't know

  xania 14:51 08 May 2009

Can you post the link to your previous problem, please.

  Catastrophe 01:14 09 May 2009


I can't find previous post but I have repeated all necessary info. I can only think it is connected with graphics. It is the 'functioning' monitor which just blinks. Everything else (except CPU) is duplicated. Everything else is 'new' or 'as new'. I come back to this voltage thing. Manual says make sure it is 1.5v. How do you tell the voltage on the card? One says type 3300. Others I can't see any clue.

  Catastrophe 01:17 09 May 2009

I can't check in Device Manager because I have no display. Only a blinking light on the monitor. Not even POST.

  OTT_Buzzard 02:03 09 May 2009

Do you get any 'beeps' on power up?

  Catastrophe 02:03 09 May 2009


From your link above:


AGP cards are backward and forward compatible within limits. 1.5 V-only keyed cards will not go into 3.3 V slots and vice versa, though "Universal" slots exist which accept either type of card. AGP Pro cards will not fit into standard slots, but standard AGP cards will work in a Pro slot. Some cards, like Nvidia's GeForce 6 series or ATI's Radeon X800 series, only have keys for 1.5 V to prevent them from being installed in older mainboards without 1.5 V support. Some of the last modern cards with 3.3 V support were the Nvidia GeForce FX series and the ATI Radeon 9500/9700/9800(R350) (but not 9600/9800(R360)).

It is important to check voltage compatibility as some cards incorrectly have dual notches and some motherboards incorrectly have fully open slots. Furthermore, some poorly designed older 3.3 V cards incorrectly have the 1.5 V key. Inserting a card into a slot that does not support the correct signaling voltage may cause damage.

There are some proprietary exceptions to this rule. For example, Apple Power Macintosh computers with the Apple Display Connector (ADC) have an extra connector which delivers power to the attached display. Additionally, moving cards between computers of various CPU architectures may not work due to firmware issues.

[edit] Use today

  Catastrophe 02:05 09 May 2009


"Do you get any 'beeps' on power up?"

No. Not with either mobo though both have power and lights on.

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