CAS latency adjustment

[PC-4LIFE]

So I found out I can increase or decrease my RAM CAS latency in the BIOS.

I want to decrease it, but should I? It's currently 15 at stock 2133mhz speed.

When I overclock the RAM higher, the CAS latency also increases, if I decrease it will it cause problems?

 

[TJ Hooker]

Well, anytime you start overclocking and playing around with RAM frequency or timings, you need to make sure it's stable. You can use something like memtest86. But no, decreasing CAS latency won't automatically cause problems, and low CAS latency is a good thing. You want frequency as high as possible and timings as low as possible, so it's something of a balancing act.

 

[PC-4LIFE]

Well, anytime you start overclocking and playing around with RAM frequency or timings, you need to make sure it's stable. You can use something like memtest86. But no, decreasing CAS latency won't automatically cause problems, and low CAS latency is a good thing. You want frequency as high as possible and timings as low as possible, so it's something of a balancing act.

Thank you. But if the timings aren't stable and the system crashes, will I still be able to boot into BIOS to reset them?

To access the BIOS, RAM is necessary.

 

[PC-4LIFE]

Well, anytime you start overclocking and playing around with RAM frequency or timings, you need to make sure it's stable. You can use something like memtest86. But no, decreasing CAS latency won't automatically cause problems, and low CAS latency is a good thing. You want frequency as high as possible and timings as low as possible, so it's something of a balancing act.

Oh and can you guide me to how to download memtest86?
I can't find a free version, it says I have to pay.

 

[TJ Hooker]

Yes, if it crashes/is unable to boot into Windows, you should still be able to get into the BIOS. If nothing else you can just clear CMOS which will restore default settings.

http://www.memtest86.com/download.htm
Free download is part way down the page.

 

[PC-4LIFE]

Yes, if it crashes/is unable to boot into Windows, you should still be able to get into the BIOS. If nothing else you can just clear CMOS which will restore default settings.

http://www.memtest86.com/download.htm
Free download is part way down the page.

So I just boot it with my USB right? There's no chance of any file corruption on my OS or BIOS?

 

[TJ Hooker]

So I just boot it with my USB right? There's no chance of any file corruption on my OS or BIOS?

Yeah, you boot from a USB that has the memtest86 image on it. Corruption from running memtest86? No, I can't see how. OS Corruption from memory overclocking? Likely possible, if you're getting memory errors and/or crashes or something. Don't think you need to worry about BIOS corruption though.

 

[PC-4LIFE]

So I just boot it with my USB right? There's no chance of any file corruption on my OS or BIOS?

Yeah, you boot from a USB that has the memtest86 image on it. Corruption from running memtest86? No, I can't see how. OS Corruption from memory overclocking? Likely possible, if you're getting memory errors and/or crashes or something. Don't think you need to worry about BIOS corruption though.

Thanks very much!

 

[PC-4LIFE]

So I just boot it with my USB right? There's no chance of any file corruption on my OS or BIOS?

Yeah, you boot from a USB that has the memtest86 image on it. Corruption from running memtest86? No, I can't see how. OS Corruption from memory overclocking? Likely possible, if you're getting memory errors and/or crashes or something. Don't think you need to worry about BIOS corruption though.

Hey sorry, I have another thing to ask.
There are 2 other things with the same clock at the CAS latency, the RAS to CAS Delay and RAS precharge.
Should I touch these at all?

Thanks.

 

[TJ Hooker]

There are 4 primary RAM timings: CL (CAS latency, most important), TRCD (RAS to CAS Delay), TRP (RAS precharge), and TRAS. Yes, in theory they all benefit from being lowered. Although to be honest, none of what you're doing is likely to be noticeable outside of memory bandwidth benchmarks. Try googling "DDR3/4 overclock guide" (depending on what type of memory you have).