Can someone help me understand what this means?

KateB

KateB

KateB

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I've been looking at motherboards and memory and came across details like this "4 x DIMM, Max. 128GB, DDR5 5200MHz upto 6400MHz (OC)" or supports 7600+(OC)/ 7200(OC)/ 7000(OC)/ 6800(OC)/ 6600(OC)/ 6400(OC)/ 6200(OC)/ 6000(OC)/ 5800(OC)/ 5600(OC)/ 5400(OC)/ 5200/ 5000/ 4800

Now the part I'm confused with is the "5200MHz upto 6400MHz (OC)" or that some frequencies have (OC) and some don't.

I understand that OC probably means overclocked but what does that actually mean in terms of buying and installing ram?

If I wanted to buy some 6000MHz ram would it be a simple plug and play or would I have to adjust some setting, possibly in the bios, or something even harder?

Thank you.
 
AMD as this example only guarantees certain RAM speeds work, anything over that 'probably' will but if not then tough, they don't guarantee it.

For example a 7800X3D only technically guarantees 5200MT/s so anything over that is 'overclocked'

Max Memory Speed
2x1R DDR5-5200
2x2R DDR5-5200
4x1R DDR5-3600
4x2R DDR5-3600

It's very likely that something like a 6000MT/s kit (especially if it says EXPO) will work just fine. You''l need to choose the correct profile in your BIOS, or, if you feel like tweaking every ounce of performance, you can set things manually.
 
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Thank you.

I "think" I understand.

So it's not just the motherboard that dictates what ram can be used but also the CPU, and in this case, regardless of how high the board states it will be limited by the CPU, which in your example the 7800X3D, is 5200MHz?

So the safe bet is to go with 5200MHz or take a chance on 6000MHz if it says EXPO?

Did I get that right?
 
Not quite.

AMD only guarantee 5200 max, if you try to use 6000 and it doesn't work then AMD will tell you to drop it to 5200 and see if it fixes the issue.
6000 will be fine in the vast majority of systems, depends on the cpu, mobo, timings etc but I'd be amazed if it didn't work.
The best cost/performance kit is commonly accepted as 6000 CL30, select the EXPO profile in the BIOS and, in 99% of cases, it'll just work.

If you want the best chance, buy the kits that are EXPO, the stuff below, C36 for cheap(er) or C30 for a little more £ but best performance depending on usage.

My basket at OcUK:

Total: £205.98 (includes delivery: £0.00)​
 
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KateB said:
So it's not just the motherboard that dictates what ram can be used but also the CPU, and in this case, regardless of how high the board states it will be limited by the CPU, which in your example the 7800X3D, is 5200MHz?

So the safe bet is to go with 5200MHz or take a chance on 6000MHz if it says EXPO?
Click to expand...
The motherboard doesn't really matter (like, at all) for the average user buying mainstream memory, but it does if you want to achieve stability at really high speeds.

KateB said:
I understand that OC probably means overclocked but what does that actually mean in terms of buying and installing ram?

If I wanted to buy some 6000MHz ram would it be a simple plug and play or would I have to adjust some setting, possibly in the bios, or something even harder?
Click to expand...
You will have to enable EXPO (EXtended Profiles for Overclocking) in the BIOS, which as the name implies: this is overclocking.

If you do NOT enable EXPO then your expensive memory will run at the default speed, which is usually just 4800.

The manufacturer of the memory rates their memory to perform at those settings and they will offer their warranty if it fails, but your CPU is only rated to operate at 5200. AMD partly do this to cover themselves because they need to support a wide range of CPUs, some of which have stronger memory controllers than others.

The official spec for Ryzen 7000 series is:
2x sticks, single rank (e.g. 2x8/2x16/2x24GB): 5200
2x sticks, dual rank (e.g. 2x32/2x48GB): 5200
4x sticks, single rank (e.g. 4x16): 3600
4x sticks, dual rank (e.g. 4x32): 3600

(All CPUs have the same spec, but you can find it here:
https://www.amd.com/en/products/processors/desktops/ryzen/7000-series/amd-ryzen-5-7600.html )

As Rob_B said, the chances of 6000 not working are somewhat slim, but it can happen and you can't return your stuff as faulty if it doesn't run stably at this speed.

As always with overclocking, you trade stability (and potentially: reliability) for speed.

Memory overclocking has got so common now that most users don't even consider it overclocking and 99% of benchmarks and reviews published online do not follow the official spec from the CPU manufacturer. Heck, even AMD and Intel often publish their benchmarks with EXPO or XMP enabled.
 
As someone who recently switched from Intel to AMD i was initially disappointed that the ram i had on intel board would not run at it's rated speed of 7600mhz, i did get it to boot at 7200mhz but it would not stay like like after a reboot it went back to 4800mhz.

After watching many videos and reading forums i settled on setting the memory to 6000mhz cl30 timings for lower latency.

I think 6000mhz is the sweet spot for AMD 7800X3D.
 
Tetras said:
The motherboard doesn't really matter (like, at all) for the average user buying mainstream memory, but it does if you want to achieve stability at really high speeds.


You will have to enable EXPO (EXtended Profiles for Overclocking) in the BIOS, which as the name implies: this is overclocking.

If you do NOT enable EXPO then your expensive memory will run at the default speed, which is usually just 4800.

The manufacturer of the memory rates their memory to perform at those settings and they will offer their warranty if it fails, but your CPU is only rated to operate at 5200. AMD partly do this to cover themselves because they need to support a wide range of CPUs, some of which have stronger memory controllers than others.

The official spec for Ryzen 7000 series is:
2x sticks, single rank (e.g. 2x8/2x16/2x24GB): 5200
2x sticks, dual rank (e.g. 2x32/2x48GB): 5200
4x sticks, single rank (e.g. 4x16): 3600
4x sticks, dual rank (e.g. 4x32): 3600

(All CPUs have the same spec, but you can find it here:
https://www.amd.com/en/products/processors/desktops/ryzen/7000-series/amd-ryzen-5-7600.html )

As Rob_B said, the chances of 6000 not working are somewhat slim, but it can happen and you can't return your stuff as faulty if it doesn't run stably at this speed.

As always with overclocking, you trade stability (and potentially: reliability) for speed.

Memory overclocking has got so common now that most users don't even consider it overclocking and 99% of benchmarks and reviews published online do not follow the official spec from the CPU manufacturer. Heck, even AMD and Intel often publish their benchmarks with EXPO or XMP enabled.
Click to expand...
I'll be getting 32GB - 2x16.

Thank you.
 
peahead said:
As someone who recently switched from Intel to AMD i was initially disappointed that the ram i had on intel board would not run at it's rated speed of 7600mhz, i did get it to boot at 7200mhz but it would not stay like like after a reboot it went back to 4800mhz.

After watching many videos and reading forums i settled on setting the memory to 6000mhz cl30 timings for lower latency.

I think 6000mhz is the sweet spot for AMD 7800X3D.
Click to expand...
Good to know, Thank you.
 
peahead said:
As someone who recently switched from Intel to AMD i was initially disappointed that the ram i had on intel board would not run at it's rated speed of 7600mhz, i did get it to boot at 7200mhz but it would not stay like like after a reboot it went back to 4800mhz.

After watching many videos and reading forums i settled on setting the memory to 6000mhz cl30 timings for lower latency.

I think 6000mhz is the sweet spot for AMD 7800X3D.
Click to expand...
What doesn’t help OP is that 6000 speed RAM isn’t 6000 mhz, it’s 6000 MT/s (3000 mhz) since it’s double data rate (DDR)

Motherboard manufacturers and people refer to RAM speed often erroneously, such as the above.
 
I really like the EXPO stuff. Back in the day I was always in BIOS manually amending settings. Now, simply pop into BIOS, change the RAM profile from Default to EXPO and select 6000 option. Then also if you want, set the performance to aggressive to help tighten up the various sub-timings and away you go. Been working really well for me - good experience so far.
 
JollyJamma said:
What doesn’t help OP is that 6000 speed RAM isn’t 6000 mhz, it’s 6000 MT/s (3000 mhz) since it’s double data rate (DDR)

Motherboard manufacturers and people refer to RAM speed often erroneously, such as the above.
Click to expand...
It's taken me a while but I'm a MT/s man now, still feels weird to say though
 
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