DDR2 Memory Issues Affecting System Reliability

Hi I have been struggling with a new system build for a while now and I am running out of ideas trying to solve the problems.

I am trying to use two KVR800D2N6/2G ddr2 modules in dual channel mode, these are listed in the bios correctly and on the whole the system works well, except I occasionaly get problems with resume from sleep:

A: the machine will restart and then take ages to resume i get a yellow triangle conflict listed against Standard Dual Cnannel PCI IDE Controller in Device Manager ( not enough resources available )
B: system runs very sluggishly
C: sometimes get Nvidia driver stopped responding.

Restarting temporarily restores normal operation

I have had a BSOD once at startup referring to a Memory Management Problem, swapping the ram sticks over ( changing slots ) on the motherboard cured this problem.

If I install only 1 ram module at a time i dont get any of the above problems, if i try to install both together in single channel mode the system goes haywire with multiple graphics driver crashes.

I have run Memtest for many hours on each module individually and together and not shown any errors.

The memory was bought at the same time and is identical and as mentioned lists correctly in the bios as running in dual channel mode.

I know that ' identical ' ram can still have differances due to manufacturing tolerances, could this be my problem, or is the motherboard being ' fussy ' unfortunately i dont have any matched spare ram to carry out comparison tests to rule out a ram problem at the moment, tempted to just go and buy some...

Event viewer does not give any real clues as to problem areas.

I have seen other threads mentiioning some of the above problems, but not seen any where all these problems are being experienced together at the same time.

My hair is going grey, please help, thanks

Thanks Dwarf, I did buy them at the same time but they were handed over to me individually and not as a packaged upgrade kit, on close inspection the serial numbers are not concurrent, so my suspicions regarding tolerances and your suggestion of timings are probably going to prove correct.
I will investigate altering the timings but this is uncharted water for me, I will read up on how to do this and experiment, thanks :)

Did'nt get any where by changing ram bios settings, robbed a matched pair of Corsair 1Gb sticks from sons pc and fitted these in mine and fitted my 2 x 2Gb Kingston sticks in his machine.

Lo and behold my original Kingstons are working perfectly in his, but the Corsairs now in mine worked stably for one day and now i am having the same problems with resume from sleep, sometimes it's ok, majority of time though when coming out of sleep, pc restarts, takes ages to run and with the same sluggish performance and as before the same conflict in device manager.

So i can only assume the Kingstons were not the real problem, have reset the bios, loaded optimised defaults, have the latest bios version, all drivers are up to date, all taken from manufacturers websites and windows is fully updated.

I am not getting BSOD's and event viewer only mentions the following Errors:

Event ID 315 Print Service x1 in last 7 days
" " 1002 Dhcp-client x3 in last 7 days
" " 3002 Microsoft Antimalwarex2 in last 24 hours

and a few warnings: 1014 DNS Client Events x1 in 24
1073 USER32 x1 in 24
1530 User Profile Service x3 in 24

Any help appreciated, thanks

yellow triangle conflict listed against Standard Dual Cnannel PCI IDE Controller in Device Manager ( not enough resources available )...

Surely this has to be primarily the problem ?, occurs every time machine does'nt resume from sleep properly.

The driver is from microsoft and dated 2006, driver update says no new driver available, and can't find anything on the Asrock website, there must be an updated driver somewhere surely ?