[Enigmatic]

Hey,

I`m looking into buying either the 3800+ or the 4400+ X2 in a few days time and had a few questions about the purchase.

1) Will there be any real noticeable difference between the 512MB cache and the 1MB cache ? I know this seems silly but I've been reading some people don't notice that big a performance boost.

2) Will I be able to get just as much power out of the 3800+ O/C wise as the 4400+? Again, from what I have been reading in other forums, the 3800+ can reach the same O/C limit as the 4400+.

Basicaly I`m just wondering if it is worth my time buying a the 4400+ or wether the 3800+ is currently a better choice when it comes to "Bang per Buck".

 

[Ste]

The L2 cache will make a small difference to apps, but nothing major really. The 3800+ normally get to around 2.6Ghz overclocked, the 4400+ maybe a little higher.
If you can get your hands on an Opteron 165 then these have the same L2 cache as the 4400+ and are about the same price as the 3800+ and normally overclock a bit higher as well. Something to consider if you can manage to find one in stock anywhere.

 

[erauman]

The extra cache may make a difference when doing extreme multitasking, but for most situations you won't notice a difference. The 4400+ also has the better E6 controller which should make it a tad bit faster clock for clock, but the price difference really doesn't justify the performance difference. I would go for the 3800+ and save the rest for another upgrade, i.e. a power supply if you plan on utilizing sli or upgrading cooling.

 

[steve!!]

well i would say to go with the dual core because the new os will apparently run ALOT better with it, also games will soon be supporting them, soo overall ne dual core u get will be more future proof at this moment in time

 

[erauman]

Quote:

Originally Posted by Ste The L2 cache will make a small difference to apps, but nothing major really. The 3800+ normally get to around 2.6Ghz overclocked, the 4400+ maybe a little higher. If you can get your hands on an Opteron 165 then these have the same L2 cache as the 4400+ and are about the same price as the 3800+ and normally overclock a bit higher as well. Something to consider if you can manage to find one in stock anywhere.

I would have suggested the same thing before AMD raised their opteron prices

 

[lonnie5000]

I would get the 4400 over the 3800. The extra cache will equate in power to about a 200 mhz gain over a chip of the same clock speed with only 512 cache. So lets say you have a chip that runs at 2.2 ghz and has a meg of L2 cache. Now you have a chip that has 512 L2 cache, it will have to run at 2.4 just to be equal to the 2.2 chip with 1 meg of L2 cache in performance. So you will always be better off with more L2 cache.

Another thing to consider is the 4400 has a higher clock than the 3800 at the same vcore. 3800=2.0 ghz at 1.35 vcore, while 4400=2.2 ghz at 1.35 vcore. So the 4400 is already the better chip. Remember the 3800 will have to run at 2.4 ghz just to equal the performance of the stock 4400. So the 4400 already has the upper hand and IMO is the best choice. Trust me I have been weighing these chips too, I'm about to buy one for myself and am leaning towards the 4400.

 

[steve!!]

does the 4400+ have 1mb of cache per core or is it 1mb in total?

 

[lonnie5000]

Quote:

Originally Posted by steve!! does the 4400+ have 1mb of cache per core or is it 1mb in total?

1mb per core. So each core has 1mb of L2 cache. Also the X2's have more L1 cache that the Opterons, 128+128 versus 64+64. Just another thing to keep in mind.

 

[Ste]

Here's a comparison benchmark between lots of the more recent CPUs. Really good for comparing the performance at stock levels in all sorts of benchmarks inc games: http://www23.tomshardware.com/cpu.ht...2=241&chart=70
It also shows you the difference between a 3500+ and a 3700+ so you can see the difference that L2 cache makes.

 

[erauman]

Quote:

Originally Posted by lonnie5000 I would get the 4400 over the 3800. The extra cache will equate in power to about a 200 mhz gain over a chip of the same clock speed with only 512 cache. So lets say you have a chip that runs at 2.2 ghz and has a meg of L2 cache. Now you have a chip that has 512 L2 cache, it will have to run at 2.4 just to be equal to the 2.2 chip with 1 meg of L2 cache in performance. So you will always be better off with more L2 cache. Another thing to consider is the 4400 has a higher clock than the 3800 at the same vcore. 3800=2.0 ghz at 1.35 vcore, while 4400=2.2 ghz at 1.35 vcore. So the 4400 is already the better chip. Remember the 3800 will have to run at 2.4 ghz just to equal the performance of the stock 4400. So the 4400 already has the upper hand and IMO is the best choice. Trust me I have been weighing these chips too, I'm about to buy one for myself and am leaning towards the 4400.

The extra cache doesn't prove that. There have been many tests showing otherwise. Only in very specific areas does the extra 512kb of cache make a significant difference. Look at pentium processors, presslers have up to 4mb of total cache ! But that certainly won't equate to 2ghz of extra performance lol

edit:and

Quote:

Originally Posted by lonnie5000 1mb per core. So each core has 1mb of L2 cache. Also the X2's have more L1 cache that the Opterons, 128+128 versus 64+64. Just another thing to keep in mind.

No they don't, each core has 64KB of both data and instruction L1 cache, so 256KB of L1 cache total on a dual core

 

[Enigmatic]

Quote:

Originally Posted by Ste Here's a comparison benchmark between lots of the more recent CPUs. Really good for comparing the performance at stock levels in all sorts of benchmarks inc games: http://www23.tomshardware.com/cpu.ht...2=241&chart=70 It also shows you the difference between a 3500+ and a 3700+ so you can see the difference that L2 cache makes.

According to that chart, both the 3800+ and the 4400+ X2 chips perform worse in Doom 3 than my current 3700+.

Whats all that about ?

 

[erauman]

Those games aren't optimized for dual cores, however the games coming out this year going to start utilizing dual cores. And when you run programs that actually utilize dual core processing the performance increase is dramatic ! Look for some benchmarks for multithreaded programs and dual cores vs the fastest single cores out.

 

[Enigmatic]

Heh, didnt look at the multi-tasking benchmanks.

All the info is cool lads, thanks alot.

I had been interested in an Oepteron 165 and know a place in the UK that currently has stock of them but as has been mentioned, the prices have risen considerably and someone on another forum mentioned they were going to be discontinued?!

My personal choice between the 3800+ and the 4400+ was going to be the 4400+ and I think I will stick whith that, the extra £100 or so doesn't really bother me and if needs must I can always flog my 3700+ [ although I probably will keep it for another machine ].

 

[lonnie5000]

Quote:

Originally Posted by erauman No they don't, each core has 64KB of both data and instruction L1 cache, so 256KB of L1 cache total on a dual core

Isn't that what I said?

Opteron's have 64k of data cache and 64k of instructrion cache, totaling 128 per core.

X2's have 128k of data cache and 128k of instruction cache, totaling 256 per core.

 

[erauman]

Quote:

Originally Posted by lonnie5000 Isn't that what I said? Opteron's have 64k of data cache and 64k of instructrion cache, totaling 128 per core. X2's have 128k of data cache and 128k of instruction cache, totaling 256 per core.

Nope, i'm afraid both have have 64k of data of cache and 64k of instruction core, totaling 128 per core.

 

[tytlyf]

Get the 170 opteron and overclock it higher than the 4400 or 3800. It's probably cheaper than the 4400 also.

But as far as your original questions...

1) Yes. There will be a difference, it's extra speed, and superpi times will reflect the extra cache.

2) No. The 3800 gets to 2.6, the 4400 gets to 2.7-2.8.

Look into the opteron duals, cheaper and will overclock higher than both.

 

[Enigmatic]

I`m only using air cooling at the moment, will a 165 still be able to make it past 2.4 on air ?

 

[tytlyf]

Quote:

Originally Posted by Enigmatic I`m only using air cooling at the moment, will a 165 still be able to make it past 2.4 on air ?

the 3800 and the 4400 should definietly make it past 2.4 on air. All the chips should, but the 165 should overclock higher than both of those, or at least to the 4400 speeds. I would look into the 170.

 

[Enigmatic]

The 170 is 4400+ prices. Is there much point in me opting for an Opteron 170 over the X2 4400+ ?

For the same price would I not be just as well off getting the 4400+ ?

 

[tytlyf]

Quote:

Originally Posted by Enigmatic For the same price would I not be just as well off getting the 4400+ ?

it's your choice, the 4400 will have a x11 multi, and the 170 will have a x10.
But the odds of a higher overclock will be in the 170's favor. I dont like X2's. I dont understand why people buy them when they have options for opterons. especially the 4200, that's a joke.