No display 4870 - got me stumped!

I really am tearing my hair out.. This one even has me stumped. I had an Nvidia GTS 250 and i sold it to buy an ATI 4870. I tried using 1x 6pin adaptor on the 4870 and it powers up, the fan goes, but i get no display, just a black screen, i cant even see the BIOS. I purchased a molex to 6pin, so i now used 2x 6pin adaptors and i get the same thing. So i took my ATI 4870 to my friends house who also has a 4870 and it works fine in his PC… What is going wrong?? Is it because i didn't UN-install my Nvidia drivers before putting in the ATI card?? I have no onboard graphics on my Asus P5QL so i can't even boot up and uninstall the Nvidia drivers that way… :-( I can't even see the BIOS, i'm literally not getting any display. any ideas?

I think my motherboard might be dead… hmm

Finally got to the bottom of it. It seems my 500w psu isn't enough to power 8gb of 1066mhz ram, an ATI 4870 as well as the processor, dvd drive etc. Process of elimination, i finally found it works when i only have 2gb ram. So that explains it, but do i really want to upgrade psu?

If I had to toss up between a new PSU or less RAM, I'd go for new PSU.

It's a bit weird that your card didn't throw up an error. I know that nVidia cards that need a lot of power go into a sort of "safe mode" and tell you that it isn't getting enough power via a popup. Some cards even have a little light on the back that goes red if it's not getting enough power. I would have thought that ati would have included something like that, but I guess not.

Anyway, I would recommend this :
http://www.ebuyer.com/product/135197

I've had one for a year now and I've had no problems. It's got a meaty fan on it, although the little blue LED is a bit unnecessary. Despite being an unknown brand, it's well built, it has a myriad of power connectors and it's got a pretty good price tag : £60.

P.S. the Hi-Power PSU comes with two 6pin PCI-E connectors as standard.

If I had to toss up between a new PSU or less RAM, I'd go for new PSU.

It's a bit weird that your card didn't throw up an error. I know that nVidia cards that need a lot of power go into a sort of "safe mode" and tell you that it isn't getting enough power via a popup. Some cards even have a little light on the back that goes red if it's not getting enough power. I would have thought that ati would have included something like that, but I guess not.

Anyway, I would recommend this :
http://www.ebuyer.com/product/135197

I've had one for a year now and I've had no problems. It's got a meaty fan on it, although the little blue LED is a bit unnecessary. Despite being an unknown brand, it's well built, it has a myriad of power connectors and it's got a pretty good price tag : £60.

P.S. the Hi-Power PSU comes with two 6pin PCI-E connectors as standard.

Hi Nahumi,

thanks for the reply. I managed to get it working with 4gb of this ram: http://www.ebuyer.com/product/141930

But i've got 4gb of it to sell now!

4gb is probably enough for me at this time. Thanks for the link for the PSU, i'll look into it.

'Bob