I did some quick testing of what could possibly be the lowest IPC processor in the universe: the 2.6GHz Northwood Celeron.
Of the benchmarks I've run on this CPU, 3DMark 2000 seems to hate it most. It just seems absurdly sensitive to L2 cache size, at least with P4-type processors. The Northwood Celeron falls so hard in this particular benchmark that an old Voodoo3 equipped Tualeron actually doesn't look too shabby!
Celeron-1400, Voodoo3-3000 OC, 512MB PC100 CL2.
Celeron 2.6GHz, Radeon 9250 128-bit PCI, 1GB DDR266 CL2:
Now you may be thinking that the PCI Radeon 9250 is holding back the Celeron a little. Well...nope. With the same video card, a 2.4GHz Pentium 4 scores around twice as high. This is just a basic 400MHz FSB P4, too. It's also running on the same motherboard.
Take a look at the massive difference in texture rendering speed between the Celeron and the P4. The P4 is over three times faster at 64MB texture rendering!
94 MHz NEC VR4300 | SGI Reality CoPro | 8MB RDRAM | Each game gets its own SSD - nooice!