[Streak 5 General] TheManii:
Introduction:

This thread suggests several build.prop entries that supposedly increase your 3g speeds:

[mod]Boosting Signal Strength (hspa/gprs)

After doing nearly 100 benches with the speedtest app, I have come to a couple conclusions:

The server your connect to for speedtest has the greatest impact on your speeds (network congestion)

The majority of the values given dont even exist by default on the device

Your battery charge might have more influence over speeds then any tweaks

Device defaults:

ro.ril.hsxpa=2
ro.ril.gprsclass=12
ro.ril.hep=" "
ro.ril.enable.dtm=" "
ro.ril.hsdpa.category=" "
ro.ril.hsupa.category=" "
ro.ril.enable.a53=" "

where " " means that the value isnt defined.

ro.ril.hsxpa: Defines weither to use UMTS, HSPDA/UMTS, or HSDPA/HSPUA respectively.

ro.ril.gprsclass: Defines what class speeds to use with edge. (12 is maximum defined in standard?)

ro.ril.hep: unknown and undefined

ro.ril.enable.dtm: Dual transfer mode (only relevent for EDGE connections, likely always enabled for devices built after 2010)

ro.ril.hsdpa.category: class 8 matches the max download rate

ro.ril.hsupa.category: class 6 matches the max upload rate

ro.ril.enable.a53: supposedly related to GSM security, no actual info (may not even exist)

Anything not listed is completely irrelevent.

Test setup:

PC on wireless-n

Streak 5 on wireless-g

Streak 5 switched to HSPA

ROM: CM7.2-rc0

Kernel: Phoenix kernel for CM7.2

BB: 406-2 (407)

Testing methodology:

Test 5/10 times on control

Make change via terminal and setprop

Enter and exit airplane mode

Do run

Undo mod and do control

Repeat for all

Do again, but make change via build.prop edits

Restart 3 times

Do run

Do control tests

Controls:

PC over landline:

Ping	Down	Up
77	2.18	4.8
63	2.11	7.98
97	2.49	5.85
63	3.07	7.6
92	3.26	7.55
49	2.71	7.17
50	2.54	7.49
55	2.8	7.28
65	2.39	7
40	2.51	4.91

Phone over wifi over landline:

Ping	Down	Up
90	2.91	7.06
54	3.23	6.53
84	3.38	7.73
72	3.7	9.03
51	4.04	7.62

Phone over 3g while charging:

Ping	Down	Up
146	0.45	0.24
786	0.29	0.18
95	0.29	0.23
966	0.28	0.29
114	0.63	0.32
886	0.27	0.15
100	0.27	0.19
837	0.38	0.34
826	0.44	0.51
896	0.21	0.56

ro.ril.hsdpa.category=8

96	1.58	1.24
106	1.56	1.56
911	1.55	1.35
101	1.96	1.82
916	1.63	1.41

Control after testing above:

125	0.48	1.01
914	0.27	0.61
110	0.69	0.9
146	0.17	0.18
108	1.1	0.73

ro.ril.hsupa.category=6

118	0.86	1.45
807	0.73	1.23
116	0.94	1.16
896	0.95	1.12
102	0.93	0.94

Control after testing above:

778	0.8	1.24
792	0.79	1.36
124	0.75	1.28
828	0.72	1.21
109	0.72	1.31

ro.ril.hsdpa.category=8 and ro.ril.hsupa.category=6

97	1.16	1.42
932	0.81	1.42
98	0.86	1.41
876	0.88	1.33
829	0.8	1.21

Control after testing above:

778	0.8	1.24
792	0.79	1.36
124	0.75	1.28
828	0.72	1.21
109	0.72	1.31

ro.ril.hsdpa.category=8 and ro.ril.hsupa.category=6 and ro.ril.hsxpa=5

126	1.16	1.41
824	0.87	1.08
795	1.08	1.06
127	0.98	1.05
116	0.73	1.18

Control after testing above:

1019	0.56	1.19
789	0.75	0.64
117	0.46	0.92
895	0.68	1.27
916	0.31	0.46

Conclusion:

A google search shows that ro.ril.enable.a53 may not even exist besides self references to it's own speed tweaks, it may very well not even exist.

The same can be said about ro.ril.hep.

ro.ril.enable.dtm may be irrelevent as DTM allows you to use voice and data at the same time, and this technology only applies to edge.

This is likely implicitly always enabled for any device that supports it past 2010, as only the earliest 3g devices may not have had support for it.

ro.ril.hsxpa=2 and ro.ril.gprsclass=12 are likely already correctly definied for it (with it being a HSPA device)

Bar ro.ril.hsdpa.category=8 and ro.ril.hsupa.category=6, the rest of them are not valid to begin with.

I was able to achieve much higher speeds by switching servers, and all tests were intentionally done on the same server for consistancy.

Those values do canonically exist on other devices, but they're never defined on the S5.

Just as much my speeds varied wildly even from control to control, as much as doubling from the lowest common to highest common.

ro.ril.hsdpa.category and ro.ril.hsupa.category might potentially give an increase in speeds, but as they dont even have default values, they might not even be valid.

I cant even reproduce some of the results from enabling only ro.ril.hsdpa.category=8, as I restart the device after each change to be sure.

I may have inadvertantly connected to a faster server for that one instance.

tl;dr: you get as much speed increases from CHANGING THE THEME ICON TO DISPLAY 4G, you can also make stuff up and pretend it does something and let the placebo effect do all the work for you.

ro.ril.hsdpa.category=8 and ro.ril.hsupa.category=6, might do something, but they could very well be invalid.