CPU/RAM Upgrade for CFD & Gaming (Ryzen 7 5800X vs. Ryzen 5 7600X vs. i5-13500)

[Bob Jim]

Budget (including currency): £600 absolute maximum, the lower the better

Country: UK

Games, programs or workloads that it will be used for: CFD & Gaming

 

Hi all,

 

I'm currently using my build from January 2016, which features an i5-6500 and 8GB of RAM. Since I built it I've updated the GPU to an RX 5600XT and have got a PCIE M.2 boot drive. My PC is now noticeably slow in games, and I am also shortly going to be using OPENFOAM CFD software for my degree, so these uses are informing my upgrades. I don't play triple A games much and only have a 1080p monitor so I am not upgrading my GPU.

 

I've identified 4 options within my budget (ideally don't want to spend it all):

• AMD Ryzen 7 5800X w/32GB DDR4-3600 CL18 RAM (£424)

• AMD Ryzen 5 7600X w/32GB DDR5-6200 CL40 RAM (£589!)

• Intel i5-13500 w/32GB DDR4-3600 CL18 RAM (£453)

• Intel i5-13500 w/32GB DDR5-6200 CL40 RAM (£533)

N.B. Mini-ITX motherboards are why these prices are so sad

 

Which of these would you recommend? I understand the 7600X is the best for gaming, but I'm pretty sure my GPU would be the limiting factor regardless?

CFD software loves threads and memory size and bandwidth, so I think that the i5 is probably best - is the DDR5 (and a corresponding nicer motherboard) worth £80, what sort of performance do you think I might see?

 

Thanks for any help or other suggestions!

[Somerandomtechyboi]

Take a look at the used market since prices tend to be alot better than new

 

Since its mini itx i assume you problably dont want a really power hungry and hot cpu so ill just suggest a 5950x based setup

 

5950x for 230£, there are also other 5950x at around the 300£ mark you can problably negociate down

 

B550i gaming edge wifi at 130£, there doesnt seem to be that many itx boards but you might have some luck on other classifieds sites like gumtree

 

Rams wise just get whatever 64gb 3200c16 kit, id reccomend crucial as they got micron rev b, not sure how capable non apu zen3 imc is at clocking dual rank, if bandwidth is all that matters it might be worth it to run desync fclk and clock as high as possible, maybe 4400 is doable but im not sure, zen3 apus (cezzane) can do 4533+ dual rank 1:1 fclk but those imcs are insane

[Bob Jim]

14 minutes ago, Somerandomtechyboi said:

Take a look at the used market since prices tend to be alot better than new

 

Since its mini itx i assume you problably dont want a really power hungry and hot cpu so ill just suggest a 5950x based setup

 

5950x for 230£, there are also other 5950x at around the 300£ mark you can problably negociate down

 

B550i gaming edge wifi at 130£, there doesnt seem to be that many itx boards but you might have some luck on other classifieds sites like gumtree

 

Rams wise just get whatever 64gb 3200c16 kit, id reccomend crucial as they got micron rev b, not sure how capable non apu zen3 imc is at clocking dual rank, if bandwidth is all that matters it might be worth it to run desync fclk and clock as high as possible, maybe 4400 is doable but im not sure, zen3 apus (cezzane) can do 4533+ dual rank 1:1 fclk but those imcs are insane

Thanks for the reply, I'm slightly concerned that used (older but higher power like 5950x) would be worse to cool as you say - the 5950X has a 105W TDP compared to i5-13500 at 65W. My case is a silverstone SG13 so I'm very limited on space for coolers (61mm vertical, currently use the stock intel cooler). That said the £230 one is an absolute steal for that performance, I have messaged them, good spot!

[brob]

1 hour ago, Bob Jim said:

CFD software loves threads and memory size and bandwidth, so I think that the i5 is probably best - is the DDR5 (and a corresponding nicer motherboard) worth £80, what sort of performance do you think I might see?

 

Did you consider the 5800X3D? Openfoam benchmarks suggest the large 3D cache really benefits Openfoam performance.

 

 

[Bob Jim]

16 minutes ago, brob said:

 

Did you consider the 5800X3D? Openfoam benchmarks suggest the large 3D cache really benefits Openfoam performance.

 

 

I didn't even know that existed! Not been paying attention to the PC market for a while. I've found one forum thread backing up the openfoam thing, where did you hear that? Seems promising but the 5800x3d does benchmark lower than the i5-13500 in multicore which you would have thought translates to worse performance.

[filpo]

29 minutes ago, Bob Jim said:

Thanks for the reply, I'm slightly concerned that used (older but higher power like 5950x) would be worse to cool as you say - the 5950X has a 105W TDP compared to i5-13500 at 65W. My case is a silverstone SG13 so I'm very limited on space for coolers (61mm vertical, currently use the stock intel cooler). That said the £230 one is an absolute steal for that performance, I have messaged them, good spot!

I'd get this cpu cooler if you have any worries Noctua NH-L9a-AM4 chromax.black 33.8 CFM CPU Cooler (NH-L9a-AM4 chromax.black) - PCPartPicker

Also btw the 13500 doesn't normally draw 65w under full load (normally more than that anyways)

[Somerandomtechyboi]

21 minutes ago, Bob Jim said:

Thanks for the reply, I'm slightly concerned that used (older but higher power like 5950x) would be worse to cool as you say - the 5950X has a 105W TDP compared to i5-13500 at 65W. My case is a silverstone SG13 so I'm very limited on space for coolers (61mm vertical, currently use the stock intel cooler). That said the £230 one is an absolute steal for that performance, I have messaged them, good spot!

Tdp is a useless metric

Irl that 13500 will draw more power once power limits are unlocked, and if you dont unlock power limits then rip performance

 

Whereas you can do abit of an undervolt on the 5950x and get lower power draw

 

16 minutes ago, brob said:

Did you consider the 5800X3D? Openfoam benchmarks suggest the large 3D cache really benefits Openfoam performance.

If the 5800x3d does actually have benifits in this workload then itd be an ideal cpu, although it runs hot it doesnt draw that much power, reason it runs hot is the insulating 3d cache trapping heat in the cpu, so the rest of your components will not run hot af cause cpu heat

 

I think youll find these also around that steal of a 5950x on the used market

[brob]

2 hours ago, Bob Jim said:

I didn't even know that existed! Not been paying attention to the PC market for a while. I've found one forum thread backing up the openfoam thing, where did you hear that? Seems promising but the 5800x3d does benchmark lower than the i5-13500 in multicore which you would have thought translates to worse performance.

 

All the AMD CPU with additional 3D cache significantly improve Openfoam performance. Unfortunately I haven't found any Openfoam benchmarks for the i5-13500.