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I recently tried to upgrade my video card from an Nvida 8600GT to an Nvidia 430GT. I am running Windows 7 with a 1.8 Core2Duo. My motherboard only has PCIe 1.0 and it has 4G of RAM. After installing the new card my computer was noticeably slower. Updated all drivers and restarted multiple times. Is my CPU to slow? Do I need a motherboard with PCIe 2? Any ideas would be helpful.

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Since you've already tried multiple drivers (my first option), I'm guessing your new card has a lot more RAM than your old card, and that you have a 32bit version of Windows.

32bit versions of Windows are limited to 4GB of RAM in total; included in this total are things like video RAM, audio RAM, and Direct Memory Accessed(DMA)-devices like your hard drive buffer. Your overall system is slower because the new card with more RAM leaves less address space for your system to use with your existing 4GB, and thus less RAM available in your system.

To fix this issue, you'll want to upgrade to a 64bit version of Windows. If you can get your hands on an installation disk for the equivalent edition (and don't forget to also match up OEM vs system builder vs retail), your existing license key should still be valid for that disk.

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To verify this I should be able to install the new card and see that I'm down on system memory by roughly the size of the video card memory? This does not sound right to me off the bat but I'll investigate. – Christian Mar 7 '11 at 18:03
Make sure you check in the operating system, not the bios. – Joel Coehoorn Mar 7 '11 at 19:09
Be careful though because in System Properties for example it will show the installed memory. I think msinfo32 should show both, otherwise try systeminfo at the command line. – Mark Sowul Mar 7 '11 at 20:36

To me it sounds like a driver issue.

Try updating to the latest driver on

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Did you plug the PCI power connectors from your power supply to the card? What is the wattage of your power supply?

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