PC World - USA (2020-10)

OCTOBER 2020 PCWorld 55

the memory bandwidth it can get so we
suspect the IdeaPad Slim 7 gets a boost from
both the additional graphics core and the
clocks plus the faster LPDDR4X/4267 RAM.
To see how much more memory
bandwidth you’d get, we compared the HP
Envy x360 13 (go.pcworld.com/x313) with its
Ryzen 5 and DDR4/3200 to the Lenovo
IdeaPad SlimPad 7 and its LPDDR4X/4267.
Don’t take this as a repudiation of the HP
because we’re really focusing on the main
memory subsystem here, and we suspect
most other DDR4 laptops would perform the
same. When we get a chance, we’ll also look
at the memory bandwidth of LPDDR4X/3733
common in Intel Ice Lake laptops use. Just to
note: Intel’s Tiger Lake will support LPDDR5X
at even higher clock speeds.
Ryzen desktop CPUs typically benefit from
increased memory clocks, but we expect the
integrated Radeon graphics in mobile Ryzen to
see an even more substantial boost. Let’s look at
how the Ryzen 7 4800U does with its faster
LPDD4X RAM. We’ll use the synthetic 3DMark
Sky Diver as a way to gauge performance.
The result is a very healthy bump in
performance over the seven Radeon cores in
the Ryzen 7 4700U, but some of that is the
increased number of graphics cores, the
increased clock speeds, and also the increase
in CPU thread count, as the score is the
overall result. Delving into just the graphics
score for 3DMark Sky Diver, it gets a little
closer. Lenovo’s IdeaPad Slim 7 and its Ryzen

Dual-channel LPDDR4X/4267 offers about 23

percent more bandwidth over a dual-channel

DDR4/3200 configuration.

Lenovo IdeaPad Slim 7Ryzen 7 4800U

HP Envy x360 13Ryzen 5 4500U

SiSoft Sandra 2020

Aggregate Memory

Bandwidth GBps

LONGER BARS INDICATE BETTER PERFORMANCE

30.9

25.2

The additional CPU, higher clocks and faster

main memory gives the Ryzen 7 4800U in the

IdeaPad Slim 7 a very healthy increase in graphics

performance.

Dell XPS 15 7590Core i9-998xq0HK

Dell XPS 15 9500 “Ultra”Core i7-10875H

MSI Prestige 14 PerformanceCore i7-10710U

MSI Prestige 14 DefaultCore i7-10710U

Lenovo IdeaPad Slim 7Ryzen 7 4800U

Acer Swift 3Ryzen 7 4700U

Dell XPS 13 2-in-2 7390 Perf ModeCore i7-1065G7

Dell XPS 13 9300 PerformanceCore i7-1065G7

Dell XPS 13 9300 DefaultCore i7-1065G7

HP Envy x360 13 PerformanceRyzen 5 4500U

HP Envy x360 13Ryzen 5 4500U

Dell Inspiron 15 7000Core i7-8665U

HP Spectre x360 13 5th GenCore i7-8565U

3DMark Sky Diver 1.0

Graphics score

LONGER BARS INDICATE BETTER PERFORMANCE

25,564

13,256

18,050

10,103

23,729

10,877

17,4 0 6

9,981

9,946

9,641

9,581

9,4 08

9,258