Introduction

If you have a motherboard based on the VIA Apollo 133A, KX133 or KT133 you may find sometimes (not in all cases) that you can’t get your graphics card to run at AGP 4x within Windows 2000, especially when using NVIDIA reference drivers. With these drivers the registry setting for AGP 4x on VIA Apollo 133A, KX133 or KT133 chipsets isn’t enabled.

Update - Due to an excess amount of TweakTown users asking how to do this same registry hack in Windows 9x we have updated this guide and included the registry hack for Windows 95, 98, 98se and ME.


This can lead to WCPUID reporting the following:



If you get this "error" when using an Apollo 133A, KX133 or KT133 on a GeForce, GeForce 2 or even an older TNT2U 4x graphics cards this can be quite irritating when you have the support of AGP4x, but can only get AGP2x. One fine example of this is my ASUS K7V motherboard... When Windows 2000 Professional is installed and any of the 5.xx ref drivers are used, my AGP speed is reported as 2x. With a simple registry trick (aka fix or hack) you can make Windows 2000 enable AGP 4x and get back to optimal speed in no time at all... WoooHoo!

Below is a copy of the registry key to edit the registry manually with or you can simply download the pre-made reg file and automatically import it into the system registry and make Windows 2000 run at 4x AGP on VIA Chipsets that support 4x AGP.

WARNING - It is no good even try this with an Apollo 133, Pro or Pro Plus chipsets as theses chipsets only support a max of 2x AGP Speed!


The Fix for Windows 2000 Only

Here is the registry information for enabling AGP 4x in Windows 2000 ONLY...

HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServices
v4Device0
"EnableVia4X"=dword:00000001

If you don’t like messing around with the registry we HIGHLY recommend you download this Registry File. Once downloaded, open it and it will automatically change the registry in seconds. Below are instructions on how to merge this file to the system registry:

1) Open 4x.reg.
2) "Are you sure you want add the information in C:4x.reg to the registry?" Click Yes.
3) Now that the information from 4x.reg has been added to the registry, reboot your PC.

Once your system boots Windows 2000 you’ll have AGP 4x enabled on your Apollo 133A, KX133 or KT133 chipsets... Below is a WCPUID screenshot of our ASUS K7V motherboard chugging along happily @ AGP 4x in Microsoft Windows 2000 Professional:




The Fix for Windows 9x Only

Here is the registry information for enabling AGP 4x in Windows 2000 ONLY...

[HKEY_LOCAL_MACHINESoftwareNVIDIA CorporationGlobalSystem]
"EnableVia4X"=dword:00000001

If you don’t like messing around with the registry we HIGHLY recommend you download this Registry File. Once downloaded, open it and it will automatically change the registry in seconds. Below are instructions on how to merge this file to the system registry:

1) Open 4x_9x.reg.
2) "Are you sure you want add the information in C:4x_9x.reg to the registry?" Click Yes.
3) Now that the information from 4x_9x.reg has been added to the registry, reboot your PC.


Uninstalling The Fix

- Download uninstall registry patch HERE for Windows 9x
- Download uninstall registry patch HERE for Windows 2000

Until next time, keep on tweaking people!