Evaluating CPU cores for optimisation - page 16

 

We clearly have a new leader - the Ryzen 3900X!

 
Aleksey Vyazmikin:

We clearly have a new leader - the Ryzen 3900X!

Not crucial, but they forgot to add the 3950X.
 
dsfx:
Not crucial, but they forgot to add the 3950X.

Adding to that. I don't like Ryzen's wide variation in average time per pass - something's wrong here.

 
Aleksey Vyazmikin:

Adding to that. I don't like Ryzen's wide variation in average single pass time - something is wrong here.

I think the 3900X and 3950X can be considered on par for average single pass. Does the disparity with other Ryzen's confuse you?

My friend with the 3900X probably got his frequency of 4542MHz from AIDA. I doubt it is real. My system reads 4600MHz, but I haven't seen it in task manager.

I got the best results with 3950X with default settings (3500MHz auto) and no MSI utilities installed. As soon as I updated the bios and this cpu isn't even in the list of updated ones, the results became worse. Tried the standard overclocking profiles - it uses a fixed frequency of max 4100MHz and the results are worse as in auto mode it overclocks to 4300MHz. Installed the Dragon Center utility for the motherboard - the results are worse. In general, I need to go deeper into settings and try overclocking, if anyone is interested. There are a lot of factors that affect the speed. I left everything by default, as I wrote above. After i7-3770 everything suits me))))


For those who are interested, here is the configuration:

The PSU is slightly different, but the same company. Didn't find mine on the list.

For those who are facing the choice of 3900X or 3950X - for the price I think the former is enough. I got a cheap mother with good VRM cooling because I consider it important for long term use of all cores at the limit. Also it has good chipset cooling and a heatsink for hot M2 from samsung. CPU cooling is air, it seems to manage it successfully, which is helped by not small case blowing by a lot of fans. The 2x32 3200 memory is the only one of its kind for an optimal price. It's not easy to find, but sometimes it's on sale. If you're not going to put 128GB RAM in, you can save money - get a miniATX mother, but with a good VRM with two slots and 64GB of this memory. The M2 evo 970 fills a large RAM capacity much faster than a normal ssd like the evo 860 for example, as I wrote earlier. I.e. it's best not to skimp on it. Anyway, that's it, glad if it helps anyone.

 
dsfx:

I think the 3900X and 3950X can be considered on par for an average single pass. Does the difference with other Ryzen confuse you?

My friend with the 3900X probably got the 4542MHz frequency from AIDA. I don't think it is real. My system reads 4600MHz, but I haven't seen it in task manager.

Yes, exactly the frequencies and performance are not clear. Why 3700x and 3800x are so much inferior to 3900x and 3950x in terms of average time per pass? The cores are supposed to be the same...

 
Aleksey Vyazmikin:

Yes, it is in terms of frequencies and performance that there is confusion. Why are the 3700x and 3800x so much inferior to the 3900x and 3950x in terms of average pass time? The cores should be the same...

Cache size.
 
Aliaksandr Hryshyn:
Cache size.

This is an interesting hypothesis - it turns out that there is a 10%-20% increase due to the third level cache.

 
Aleksey Vyazmikin:

This is an interesting hypothesis - it turns out that there is a 10%-20% gain due to the third level cache.

32Mb vs 64Mb

 
Aleksey Vyazmikin:

This is an interesting hypothesis - it turns out that there is a 10%-20% increase due to the third level cache.

In general, it's better to work with code fragments not exceeding this size.

Recently I was working with strings on µl. Just adding characters to the end of a string. It was around 500 000 characters. (500k bytes).

The processing was phenomenally slow, either through a special function or otherwise.

However, it did take some time to add separate lines within 32Kb through a simple "+" operator without code optimization mode. And then adding them together gave a speed gain almost 10 times

 
Aleksey Vyazmikin:

This is an interesting hypothesis - it turns out that there is a 10%-20% increase due to the third level cache.

I noticed a long time ago that speed is affected by cache size and memory access speed. The 2990wx has just high delays when accessing memory, but the speed is high at that. Apparently it's not just the speed, but in combination with latency and cache organization that affects it.