3DMark05 measures performance by simulating DirectX 9.0c games, i.e., using Shader 3.0 model. This programming model is used by games like Far Cry. This programming model is used by GeForce series 6 and 7 from NVIDIA and Radeon X1000 series from ATI.
It isn’t fair to use this program to measure the performance of on-board video, as none of them is based on this programming model. But we used it anyway to see how was the 3D performance Gigabyte GA-8I945GMH-RH using a real video card. You can find the results below.

Motherboard	3Dmark05 (Build 1.2.0)	%
Gigabyte GA-8I945GMH-RH (Intel i945G) DDR2 + GeForce 6200 PCI-E	1537	+145.53
Intel D915 GEVL (Intel i915G) DDR2 + GeForce 6200 PCI-E	1535	+145.21
Gigabyte GA-8I945GMH-RH (Intel i945G) DDR2 + GeForce 6200 TC	1315	+110.06
ASUS P5RD1-V (ATI Xpress 200) DDR on-board	746	+19.17
Gigabyte GA-8I945GMH-RH (Intel i945G) DDR2 on-board	626
Foxconn 865G7MC-ES (Intel i865G) DDR + GeForce FX 5200 AGP	263	-138.02

From all motherboards with on-board video we included in our tests only Gigabyte GA-8I945GMH-RH (Intel 945G - GMA 950) and ASUS P5RD1-V (ATI Xpress 200) were capable of running 3DMark05, even then achieving very low results. ATI’s on-board video solution was 19.17% faster than Intel’s on this test.

A GeForce 6200 with 128 MB and 128-bit memory interface was 145.53% faster on 3DMark05 than the on-board video from Gigabyte GA-8I945GMH-RH. A GeForce 6200 TurboCache with 64 MB and 64-bit interface was 110.06% faster than the on-board video from the reviewed motherboard.

With a GeForce 6200 with 128 MB installed, Gigabyte GA-8I945GMH-RH achieved the same performance of Intel D915 GEVL (Intel i915G) motherboard with the same video card installed.