I'm setting up a new HP zBook 17 g2 and am getting very poor DPC latency performance (> 6000 us) when running from the PCIe SSD.
I've re-installed the OS (Win 7 64 bit) on both the PCIe SSD and a SATA HDD and the DPC latency performance is fine when running from the HDD (50 - 100 us) but horrible when running from the PCIe SSD (> 6000 us). I've updated the BIOS and tried every combination of driver and component enabling/disabling I can think of. The DPC latency is extremely high from the initial Windows install with no drivers installed. Adding drivers seems to have no effect on the DPC latency.
Before purchasing the laptop I found this review:
http://www.notebookcheck.net/Review-HP-ZBook-17-E9X11AA-ABA-Workstation.106222.0.html
where the DPC latency measurement (middle of the page) looks OK. Of course, this is the prior version of the laptop and I believe it does not have the PCIe SSD. Combining that with the fact that I get fine performance when running from the HDD I am led to believe that the PCIe SSD is the cause of the problem.
Can anyone think of what could be the problem? More importantly, any thoughts on how to fix it?
Thanks in advance,
rgames
I've re-installed the OS (Win 7 64 bit) on both the PCIe SSD and a SATA HDD and the DPC latency performance is fine when running from the HDD (50 - 100 us) but horrible when running from the PCIe SSD (> 6000 us). I've updated the BIOS and tried every combination of driver and component enabling/disabling I can think of. The DPC latency is extremely high from the initial Windows install with no drivers installed. Adding drivers seems to have no effect on the DPC latency.
Before purchasing the laptop I found this review:
http://www.notebookcheck.net/Review-HP-ZBook-17-E9X11AA-ABA-Workstation.106222.0.html
where the DPC latency measurement (middle of the page) looks OK. Of course, this is the prior version of the laptop and I believe it does not have the PCIe SSD. Combining that with the fact that I get fine performance when running from the HDD I am led to believe that the PCIe SSD is the cause of the problem.
Can anyone think of what could be the problem? More importantly, any thoughts on how to fix it?
Thanks in advance,
rgames
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