P35-ds3l trouble

[TalisX]

Hello, I previously had a perfectly functioning 3.6 GHz OC on with my Gigabyte p35-ds3l, then i upgraded my graphics card. It was an 8800gt and I upgraded to an hd4870. As it is using the exact same settings as my 8800gt in bios I can't get it to post. Any suggestions?

 

[Lmeow]

Did you remember to remove the previous graphic card drivers?

 

[Shadow703793]

^ Yup. That's probably the case.

Also make sure everything is plugged in (esp. 6 pin PCIe),etc

 

[TalisX]

I have 2 6 pin PCIe plugs connected to my gfx card. I totally uninstalled 8800gt using driver sweeper. When i reinstall the 8800gt, however, it will post normally with the OC settings, earlier I pulled the 8800 back out after getting it to post, then reinstalled the 4870. This time it posted and seemed to run fine until I had the realtek hd audio error in Bad Company 2 had to reboot. Upon rebooting it couldn't post and reset bios.

 

[TalisX]

Kinda frustrating...if i set voltages to auto it'll start to post(shows text on screen for like 2 seconds) then cuts back off and reverts to stock. Runs perfectly fine at stock speeds and with the 8800 gt it was totally stable overclocked with my settings.

 

[Shadow703793]

^Hmm.... this seems like a PSU issue.

 

[TalisX]

ok...so... I have had another development. I remembered seeing someone say that if you unplug your usb devices sometimes that helps and/or is needed when over clocking. So i tried it and it worked!? posts as long as I unplug my usb hdd and wireless gaming receiver from windows. Also i thought the same, shadow, that is why last week i upgraded from a 500W Power Supply to a 620.

 

[Shadow703793]

^^What model?

 

[TalisX]

it's an Antec Neo Eco 620c as far as I know very very good PS.