We have test latest xen on VT platforms with Intel 915/E8500 chipset 
and Here is the test summary:
 
 
IA-32: 
    Build&Boot SMP xen0 without 
problem
    Can bootup unmodified 2.4/2.6 linux on VMX domain 
    Can bootup unmodified Window 
XP/XP-sp1/XP-sp2/XP-Embedded/2003
    Can bootup VMX & Xen 
with different configuration
    Part of LTP runs well in VMX 
domain(2.6)
 
IA-32e: 
    Build&Boot SMP xen0 
without problem
    Can bootup unmodified 2.6 linux on VMX 
domain 
    Can bootup unmodified Window 
XP/XP-sp1/XP-sp2/XP-Embedded/2003
    Can bootup VMX & 
xenU with different configuration
    Part of LTP runs well in 
VMX domain(2.6)
 
issues:
 
    - can not create IA-32e VMX which has >=4GB memory in 
IA-32e platform.
    - vcpu-pin on VMX guest will hang service 
OS.
 
 
For details:
--------------------------------
Platform: 
IA-32
Default guest OS: IA-32, 2.4 kernel
 
1, one vmx with memory 
128        PASS
2, one vmx with memory 
256        PASS
3, one vmx with memory 
512        PASS
4, one xenU 
create                
PASS
5, 2 vmx and 2 xenU coexist       
PASS
6, four vmx 
coexist               
PASS
7, network in VMX 
domain          PASS
8, network 
in XenU domain         PASS
9, one 
window 
domain              
PASS
10, IDE test in VMX domain        
PASS
11,part LTP test in VMX domain    
PASS
 
 
Platform: IA-32e
Default guest OS: IA-32e, 2.6 
kernel
 
 
1, one vmx with memory 
128        PASS
2, one vmx with memory 
256        PASS
3, one vmx with memory 
512        PASS
4, one xenU 
create                
PASS
5, 2 vmx and 2 xenU coexist       
PASS
6, four vmx 
coexist               
PASS
7, network in VMX 
domain          PASS
8, network 
in XenU domain         PASS
9, one 
2.4 IA32 VMX domain        PASS
10, one 
2.6 IA32 VMX domain       PASS
11, IA-32 2.4 
and 2.6 VMX coexist PASS
12, IA-32 and IA-32e VMX coexist  
PASS
13,Part LTP test in VMX domain    PASS
14, one window 
domain             
PASS
 
 
 
Thanks and best 
regards
Alex shi