Lab Update: AMD Athlon II X4 620 and Lynnfield Memory
Posted on 9th Oct 2009 at 11:17 by Richard Swinburne with 14 comments
Yes, we're a bit behind, but the Radeons arrived and deciding between a £75 quad core or the latest and shiniest DirectX 11 graphics cards is like wondering whether we'd rather eat out at Marcus Wareing, or go to a burger van at a motorway lay-by.
For the record, The Berkeley is fantastic.
Anyway, now the Radeons are mostly done with I've had time to crack on with AMDs cheap chip; the 620. But, why does anyone need a sort-of-fast quad core? Given previous slower quad cores from AMD have been nothing more than a wet fart, I don't really have much hope for the 620 and compared to a MHz-laden dual core like the Phenom II X2 550 or Athlon II X2 250 it does seem in need of a change of underwear.
However, the L3 cacheless 620 does seem to overclock quite happily. A nice, round 250MHz HT clock gives 3.25GHz, and we've squeezed it up to 275MHz, which makes a tasty 3.575GHz. Ideally AMD really needs a Black Edition Propus core - but that risks cannablising its Phenom II X3 720 Black Edition or even its full fat Phenom II X4s.
I've spoken to some people who swear by the 620, and understanding the circumstances in which they use it - like a home theatre - I can appreciate that. Using it with the highly threaded CoreAVC codec, for example, would probably work wonders. I still don't think its a substitute for a fast dual core in a budget build though; the Phenom II X2 550 Black Edition is the same price and comes unlocked too.
On the topic of overclocking, we're using the MSI 790FX-GD70 as our standard AM3 CPU backbone and for the first time I've actually used the little OC twisty-button-thing. Clock up the HT to a safe but high degree, then gently ease it up further using the knob, while watching all the respective clocks increase in CPU-Z while concurrently testing stability in between. It's far more economical than going back to the BIOS all the time, though the quality of that little knob leaves a lot to be desired. It feels cheap and plasticy (because it is) and doesn't register every click that it's turned. It also can't be turned DOWN either, just up, which is annoying if you push it a shade too far.
Finally, a Lynnfield Memory Performance feature is on the cards shortly too: we're aiming to test high to low memory speeds at different CAS latencies on a Gigabyte P55-UD5 to see what makes a difference, if any. After chatting with the lead FAE at a popular memory company recently, she claimed the EVGA and Gigabyte UD5/6 boards were notably better for overclocking memory, so that's why we're using it.
We've also got a load of memory in from lots of manufacturers so you can vote which bling you like most. All for a bit of fun since in reality heatspreaders/sinks make as much difference as the paint on your car will increase it's speed.
That and Windows 7 launches in a few weeks! Woo!