Can no longer overclock CPU after installing MSI 4890 Cyclone

[pouraduff]

I recently purchased a MSI R4890 Cyclone OC video card to replace my XFX 8800 GT.  With the 8800 GT, I was able to overclock my E8400 to 3.6 GHz from 3 GHz stock.  After I installed the 4890, my PC will no longer accept any CPU overclock.  When I power on my system with any OC, the PC will start to come up, power cycle itself before POST and reset the BIOS back to default clock speeds, and finish booting into Windows XP Home.  Even with no OC, the PC seems to take longer to POST than with the 8800 GT.

I uninstalled the Nvidia driver before installing the 4890 and installed the latest ATI driver v. 9.8.  I flashed my motherboard's BIOS to the latest version, set it to the defaults, and then put my OC settings back in.  However, that didn't help.  Everything works fine if I put my 8800 GT back in.

I read in the NCIX forum that someone else had this exact same problem with his 4890 Cyclone, and he had a different model Gigabyte board.  I'm wondering if there is some sort of incompatibility.  Thanks for any help.

[Pottypete]

Hi,
Mobo Model no would help,
Intel or Amd cpu?
Nvidia chipset? don't much like ati drivers,
regards

[pouraduff]

The system info is in my signature.

[pouraduff]

Does anyone know of anything I can try or need any additional info?  I reinstalled the XFX 8800 GT and can overclock without any trouble and get faster boots.  I may just have to sell my MSI R4890 and get something else.

[Pottypete]

Hi,
Have you checked out the latest drivers for yor card,
Def seems like driver problem,
Try system restore,  before you uninstalled the old drivers, and install new driversfor the MSI  over the top,
worth a try,
Regards

[MJA]

I have the same problem

PottyPete,it has nothing to do with gfx card drivers or the operating system,it is a BIOS/self check problem related to specific Radeon 4890's
With mine it causes a longer POST time and fails POST with a double boot when any FSB,Memory timings etc are changed from Auto to manual in the M.I.T

Basically what happens is,with the R4890 plugged in  it will fail a POST with a double reboot whenever certain  changes are made in the M.I.T section of the BIOS.It will not tolerate virtually any timing changes or settings taken off AUTO control, apart from some voltage changes (eg DDRAM voltage).Even enabling manual FSB control causes a double reboot,even if the FSB is inputted/left at standard.You can change to a lower multiplier (underclock CPU ) but no FSB changes  ,even when it is set manual instead of Auto with default CPU FSB.Same thing with Ram timings or FSB to Ram multiplier.On re-entering the BIOS after a double reboot then going into M.I.T part of BIOS  it says something like "your sytem has failed to boot due to voltage or overclocking",but it still does this even if you make changes in there  to default settings ie take certain settings off Auto or manually set FSB by keying in value.

When i was using a Radeon HD4850 I had a reliable overclock to 3.6GHZ with 1:1 ratio ,400mhz FSB ,ram timings manually set to 4-4-4-12.No BIOS voltage tweaks required
This was with pairs of mismatched memory modules as well (2x PC6400C4 and 2xPC8500C5') set to 800mhz

Since installing an MSI R4890 Cyclone OC it has a  longer POST time (when it boots with stock/ std settings ie F7 optimised defaults)
Now it will also  not tolerate any changhes in the M.I.T bios section
Here is a link to same type of problem in another forum
http://forums.ncix.com/forums/?mode=showthread&forum=101&threadid=2061883&pagenumber=1&subpage=1



My system specs are Gigabyte EP45-DS3R motherboard  F10 bios (also tried F11c)
Core 2 Duo E8400
MSI Radeon R4890 Cyclone OC  gfx card (was ok with Saphire HD4850 or Gigabyte HD4850)
Currently 2Gig of Corsair PC8500
 Hyper type R 580watt PSU

Martin