L4IPEM v1.0, maximum CPU and HDD supported information as below,
HDD: 250G
CPU: Pentium 4 400Mhz FSB (256K/512K L2 cache) CPU – 2.0G 
          Pentium 4 533Mhz FSB (512K L2 cache) CPU – 2.8G 
          Pentium 4 533Mhz FSB (512MB/1M L2 cache) HT CPU – 3.06G
          Celeron 400Mhz FSB (128K L2 cache) CPU – 1.8G

Yes, L4IPEM v1.0 can support INTEL Hyper-Threading technology without problem. If you install a Hyper-Threading CPU such as P4 3.06G ,  there is "Hyper-Threading technology" item in the BIOS to let you choose to enable or disable this new exciting feature.

Yes, the L4IPEM V1.0 comes with Intel ICH4 chip which supports USB 2.0.

Yes, the L4IPEM V1.0 supports hard drive capacity up to 160GB.

No, the L4IPEM V1.0 supports AGP mode up to 4X (1.5V only). You can install an AGP 8X card on this MB but the card will run with AGP 4X mode.

No, the L4IPEM v1.0 only supports to DDR333 maximum.