Need help with ram timing PLZ

[zimasta]

Hi there i bought the 990fx ud7 and have 4 gskill f3-12800cl7d-4GBRAM and I put two in runs fine at 1600 byt put four in wont get boot what is a good timing to be able to put 4 at 1600  plz help me thy and have a good day

[autotech]

First off welcome to the forums. Please read the following post to better understand your ram and an amd processor.

http://forum.giga-byte.co.uk/index.php/topic,2515.0.html

Kudos to absic for putting that thread together.

now to the next. 7-8-7-24- 2n is what they are rated at that being said download cpud and it tells you where your timings are which is which. So you have 4 x 2 gig sticks id put the 2 in and boot it then run memtest on them for at least 10 passes if they pass take them out and swap them with the other two sticks you left out. Run memtest another 10 passes. Please report your results back so we can further diag your problem.

Could be bad sticks, you could have them set to ganged in bios instead of unganged, ( cpud will also tell you this ).   Make sure voltage is set to 1.6 default is 1.5 usually. You can try upping the voltage a little at a time to see if you need to take it all the way to 1.6.

Might be you need to set timings to 9-9-9-24 that seems a good speed for 1600 but then again if you run them at 1333 at 7-8-7-24 you will more than likely get as good or better performance because your timings are lower. 

Alot of variable like i said report back with the info also what the rest of yor build is cpu, type hard drive and so on please and again welcome.

[kosobai]

From the web-site:

"*G.Skill guarantees 2 Dimms dual channel operation would reach announced specification."


http://www.gskill.com/products.php?index=386


You are trying to run four sticks, which may be the problem. My suggestion: set the RAM to 1333MHz and grab a copy of CPU-Z. Note the timings listed in CPU-Z and, in the BIOS, lower the timings to the lowest figures displayed by CPU-Z. If it won't boot afterwards, update the timings to the next lowest and so on until it boots.

For the record, my four sticks achieve higher benchmarks in Geekbench with the timings set to 7-7-7-19-26-1T @1333MHz than two sticks did with 9-9-9-24 did @ 1600MHz.

I'm using UMAX RAM.

[zimasta]

ok so i go all four stick to run at 9-9-9-24 so im happy with that  ty very much for your help and ty for the welcome!

[autotech]

You are more than welcome. If there are any more problems we all will try to help as best we can.