System will not post with upgraded graphics card

I have been trying to upgrade my graphics card. system is well behaved with old simple graphics card a GB radeon H6450.

A month or two back I tried a GB GTX 750 card and had the same problem. Today I bought a GB R7260X thinking maybe it would do better with a Radeon card rather than a nVidia. But no luck.

Change out the card connect up the power supply and it won't even post, the fans come on but no beep. Change back to the old card, it leaps straight into life.

Differences are old card is single slot with no fan, a very basic card. New cards both take up two slots on the back panel, much larger with big fans. Old card was bus powered new card 1 the GTX750 was aso bus powered. The R7260X has a 6 pin connector. Both new cards fit in the case just fine.

Where do I start with troubleshooting this if the system won't even post? I have to think the old card connects fine but the new cards don't due to some sort of Mboard damage or maybe a short with the larger card?? The GTX 750 I returned and was given a refund. they tried it in the shop and it booted first time.

Appreciate any advice.

Chris Ross

Hi,

Is this the right place to post this issue?

I have basically decided to replace the motherboard. Unfortunately being a socket 1155 processor it also means I need a new processor as very few boards are now available in 1155 socket. I think I'll recycle the old processor into another computer, I can pick up a cheap 1155 board quite easily to make a PC for my mother in law.

The reasoning is that it'll only boot with the old card, a couple of times it refused to boot with old card and I played with the monting plate screws to ensure it didn't side load the card and after that it booted, seems like a problem with the PCI-E 16x socket. I also tried with now graphics card after enabling on board graphics and it also refused to boot.

Any further thoughts?

thanks,

Chris Ross

I had a new Asus straight out of the box a few years back and had to update its BIOS before it would recognize a card not even as new as itself even !

Thanks for the reply, suppose it's possible but the board sometimes fails with a more basic card in place and is fixed by making sure there's no side strain on the card when screwing in the back panel mount. The new card is bigger and takes up two slots, so presumably I can't get it to a position where the fault doesn't occur. I also tried the onboard graphics (turned it in in BIOS first) which has worked in the past and it failed with no card in the system.

Well not really solved but closed as I ended up upgrading motherboard. recycled everything else into a new PC.