Well the mistake was ....... when i installed XP in the olden days; i set the SATA HDD settings in BIOS as IDE (it emulates as IDE so XP can see it). However, afterwards, I completely forgot about it, and when moved to 7 the same thing passed on to the new OS. Now, when i tried to fix it (without having to reinstall) I pretty much screwed it up. Anyway, the long and the short of it, I restored it back to pre-destruction situation
Now, to your minidumps; both of these leads to 0x1000008e, which is KERNEL_MODE_EXCEPTION_NOT_HANDLED bug check and is a very common.
Any thing of the following can cause this:
1. Hardware incompatibility (make sure that any new hardware installed is listed in the Microsoft Windows Marketplace Tested Products List).
2. Faulty device driver or system service. A faulty device driver or system service might be responsible for this error.
3. Hardware issues, such as BIOS incompatibilities, memory conflicts, and IRQ conflicts can also generate this error.
Possible solutions include:
1. Ensure that enough hard disk space is available.
2. Update your motherboard's bios.
3. Update your Graphic Drivers / chipset drivers
However, Microsoft also lists that you may have to replace your graphics card if updation of drivers doesn't work.
Check the System Log in Event Viewer for additional error messages that might help identify the device or driver that is causing bug check.
Lastly, I'll advise you to again run memtest; let it run for the whole night (12+ hours).