It ain't the 3D Prophet DDR-DVI. I'm using the Hercules 5.22 drivers and the UT 4.13 patch and have no problems. If you're using them, it's a mobo issue. Maybe one of those VIA/Athlon issues.
I'm running a BX mobo and have the 3D Prophet DDR-DVI O/C'ed to 160/350 with the CPU running at 970 MHz. With UT set at 1024x768 at 32-bit color, I'm averaging fps in the mid to upper 70's with no lag.
1.Old Antec Case, Asus PC-DL, 2 x 1.6 LV D1 Xeons @ 3 GHz, 2GB Corsair PC3200 @ 200 MHz, Chaintech 6800 128MB AGP
2. Old Crap Beige Case, Gigabyte GA-H55M-S2H, Core i3 530, 4GB CL8 OCZ DDR3-1600, eVGA GTX465
3. Asus Pundit mATX Case, MSI AMD Zacate E350/dual core E350IS-E45 mini-ITX, 4GB CL9 Crucial Ballistix DDR3-1333, LG Blu Ray/HD DVD & DVD Burner