ESXi Hardware Requirements (4.0 u2)
Except from page 13...
VMware ESXi 4.0 will only install and run on servers with 64-bit x86 CPU's
Known 64-bit processors
All AMD Opterons support 64 bit.
All Intel Xeon 3000/3200, 3100/3300, 5100/5300, 5200/5400, 7100/7300, and 7200/7400 support 64 bit.
All Intel Nehalem support 64 bit.
2GB RAM minimum <-- you're short on this to start with.
Chances are, your processor won't fly right... Post up the actual processor designation so it can be checked, or look on ark.intel.com to see if it has the correct technologies built into it... You could check your bios to see if it's a 64 bit processor, and to ensure that it has the Intel Virtualization setting that can be enabled on it. If it doesn't, then you have little, to no, chance of getting ESXi 4.x to install onto the system...
VMware VCP4
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